The Grand Prix was contested by eleven teams with two drivers each. The teams (also known as constructors) were Ferrari, McLaren, Williams, Benetton, BAR, Jordan, Arrows, Sauber, Jaguar, Minardi and Prost. Before the race, both the Drivers' Championship and Constructors' Championship were already settled, with Ferrari driver Michael Schumacher having claimed the Drivers' Championship two rounds earlier in the Hungarian Grand Prix and Ferrari took the Constructors' Championship at the same event, with McLaren too many points behind to be able to catch them.
After the Belgian Grand Prix on 2 September, the teams conducted mid-season testing at various European race circuits between 4–7 September to prepare for the Italian Grand Prix at the Autodromo Nazionale Monza. Ferrari, Williams, BAR, Jordan and Minardi tested at the Mugello Circuit. Rubens Barrichello for Ferrari set the fastest times on the first and second days. The second day of testing was disrupted on six occasions after BAR test driver Takuma Sato went off the circuit, suffered an electronic control unit failure and had a malfunctioning anti-stall system. BAR driver Olivier Panis and Minardi driver Alex Yoong both had problems with their clutch and gearboxes. On the final day Michael Schumacher set the fastest lap of 1 minute and 24.226 seconds, four-tenths ahead of Panis. Ferrari test driver Luca Badoer spent three days at his team's private test track the Fiorano Circuit where he did practice starts as well as testing of launch control and traction control.
After the September 11 attacks on New York and Washington D.C., Formula One's governing body, the Fédération Internationale de l'Automobile (FIA) announced that the Italian Grand Prix would go ahead as scheduled. Ferrari president Luca di Montezemolo said that his team would approach the race as a normal racing event instead of a traditional Ferrari festival. Furthermore, di Montezemolo stated Formula One should continue its normal schedule and not cancel races. Additionally, the Automobile Club d'Italia urged fans and spectators to behave "in keeping with the gravity of the situation and in collective participation in the pain of American citizens." Podium celebrations were also cancelled and all pre-race ceremonies including a flypast by the Italian Tricolour Arrows display team were called off. Three teams altered their car's liveries as a mark of respect. Ferrari stripped their cars of all advertising and painted their nose cones black. Jaguar fitted black engine covers to their R2 cars on Saturday morning, and Jordan sponsor Deutsche Post replaced its branding with the flag of the United States on the Jordan cars engine cover on Sunday morning. Michael Schumacher was reluctant to take part in the race and said in 2002 that he felt it was a "bad sign" to be driving after the September 11 attacks.
There were two driver changes heading into the race. The Minardi team replaced regular driver Tarso Marques with Yoong. Yoong received backing from the Magnum Corporation and was granted a super licence after a two-day test at the Mugello Circuit. He became the first Malaysian driver to compete in Formula One. Marques was kept on as the team's test and reserve driver, and assisted with developing the Minardi PS02. Czech Formula 3000 driver Tomáš Enge (who had been signed as the test driver for Prost) replaced Luciano Burti who had been recovering from an concussion and bruising he sustained in an accident at the previous race in Belgium.
Due to the configuration of the Autodromo Nazionale Monza, with its high average speed, the teams set up their cars to produce the minimum amount of downforce possible. Williams introduced a revised FW23 specification for Montoya after one was used by Ralf Schumacher in Belgium. Williams equipped the earlier aerodynamic package on Ralf Schumacher's car on Sunday morning. Benetton brought a new front wing and Ferrari debuted a new engine specification with improved aerodynamics.
Four practice sessions were held before the Sunday race, two each on Friday and Saturday. The Friday morning and afternoon sessions each lasted an hour; the third and fourth sessions, on Saturday morning, lasted 45 minutes each. The first practice session was moved from the usual start time from 11:00 Central European Summer Time (UTC+02:00) to 10:50 to comply with a planned silence for one minute that was observed at 12:00 throughout Europe. Michael Schumacher set the pace in the first practice session, which took place in dry weather conditions, with a time of 1:25.524; David Coulthard had the second-fastest time. Barrichello was third fastest, ahead of Nick Heidfeld (who crashed his car at Variante Ascari) in fourth. Mika Häkkinen recorded the fifth fastest time, with Jenson Button in sixth. Kimi Räikkönen, who was seventh fastest, collided with a barrier at Variante Goodyear which removed his front-right wheel. Ralf Schumacher, Jarno Trulli and Pedro de la Rosa rounded out the session's top ten fastest drivers. Arrows driver Jos Verstappen did not set a lap time because he collided with a tyre barrier at the Curva di Lesmo early in the session. In the second practice session, where a brief rain shower hit the circuit early in the session, Ralf Schumacher set the fastest time of the day, a 1:24.667; Montoya had the second fastest time despite going off the circuit during the session. Michael Schumacher (with a time of 1:25.131) was third fastest, ahead of de la Rosa. Barrichello, Häkkinen and Coulthard filled the next three positions. Despite not going onto the circuit, Heidfeld was the eighth fastest driver. Alesi and Heinz-Harald Frentzen (who slowed in his car and went off the circuit and slid wide of the track and avoided colliding with the barriers) followed in the top ten.
Montoya took the fastest lap of the third practice session, a 1:25.558 which was held on a damp track. Barrichello was second fastest with a time 0.336 slower than Montoya. de la Rosa was running quickly and set the third fastest lap, a 1:26.542. BAR drivers Villeneuve and Panis set the fourth and fifth fastest times. Räikkönen, Eddie Irvine, Verstappen, Enrique Bernoldi and Heidfeld rounded out the top ten. Giancarlo Fisichella, Yoong, Jenson Button, Jean Alesi, Michael Schumacher, Coulthard, Häkkinen and Fernando Alonso did not set lap times during the session. The circuit dried up for the final practice session where Michael Schumacher had the fastest lap of the weekend so far with a 1:23.178; Barrichello had the fastest time when circuit conditions improved but fell to fourth. The two Ferrari drivers were separated by Montoya and Trulli. Coulthard was fifth quickest with Ralf Schumacher sixth. Heidfeld, Häkkinen, de la Rosa and Räikkönen rounded out the top ten drivers ahead of qualifying. Enge spun but regained control of his car.
Saturday afternoon's qualifying session lasted for an hour. Each driver was limited to twelve laps, with the starting order decided by the drivers' fastest laps. During this session the 107% rule was in effect, requiring each driver to remain within 107% of the fastest lap time to qualify for the race. The session was held in dry weather conditions. Montoya clinched his second consecutive pole position and his third of the season with a time of 1:22.216. Although he was happy with the feel of his car, he did not feel confident that he could take pole position. Montoya was joined on the front row by Barrichello who recorded a lap 0.312 seconds slower and also went off into a gravel trap during qualifying. Michael Schumacher qualified third and admitted to making a mistake on his third run which prevented him from setting a quicker time. Ralf Schumacher had balance issues which meant his car alternated between understeer and oversteer en route to fourth position. He also managed three clear runs before his fourth was disrupted by a yellow flag. Trulli qualified fifth and was delighted with his car and tyres. Coulthard qualified in sixth position and felt his car's balance was good although felt it difficult to push hard and achieve ideal grip. Häkkinen took seventh and ran wide at the exit of Curva di Lesmo on his final timed run and crashed heavily into a barrier which resulted in a large amount of damage to the front and left side of his car. Häkkinen was unhurt but the crash caused qualifying to be suspended for thirteen minutes.
The two Sauber drivers were eighth and ninth with Heidfeld in front of Räikkönen; Heidfeld was happy with his position after losing track time on Friday while Räikkönen complained that he had been blocked by Fisichella who was on an out lap. de la Rosa rounded out the top ten qualifiers and was happy after Jaguar engineer Humphrey Corbett corrected an issue with understeer on de la Rosa's car. Button took eleventh position and reported that his Benetton was well balanced. Frentzen took twelfth and said his qualifying position was more significant than his fourth-place finish in the Belgian Grand Prix. Irvine struggled with brake balance which shifted towards the rear of his Jaguar which meant he managed thirteenth. He also was unable to set a faster time after Olivier Panis blocked him by driving to the first corner apex and stopped his car. Fisichella used his Benetton team's spare car because his race car developed an hyradulic failure in practice but had an engine issue in the spare car which restricted him to fourteenth. BAR drivers Jacques Villeneuve and Panis took the fifteenth and seventeenth positions and both reported that there was a lack of aerodynamic grip but mechanical grip was fine. The two were separated by Alesi in the slower of the two Jordan cars and described his session as " the worst qualifying session I could imagine on a circuit which love" because he had brake balance and handling issues. Verstappen and Bernoldi took the eighteenth and nineteenth positions for the Arrows team. Enge set the twentieth fastest time in his first Formula One qualifying session, and had two engine problems in both his race car and the spare monocoque tuned for Frentzen. The two Minardi drivers qualified at the rear of the field with Fernando Alonso ahead of Yoong; both drivers stopped on their out laps with gearbox actuator failures and were required to share the spare Minardi car.
The drivers took to the track at 09:30 local time for a 30-minute warm-up session. It took place in sunny and warm weather conditions. Michael Schumacher maintained his good performance, setting a time of 1:26.029. Coulthard was the second-fastest driver. Montoya was third, two-tenths of a second behind Schumacher. Barrichello completed the top four fastest drivers. After the end of the warm-up but before the race, a second minute of silence was held at the end of the Drivers' Parade.
The race started at 14:00 local time. The race was held in sunny weather conditions; the air temperature was 19 °C (66 °F) and the track temperature 26 °C (79 °F). During the buildup to the race, Michael Schumacher attempted to organise a pact that would see no overtaking at the first two chicanes. The plan failed, with Villeneuve, Benetton team principal Flavio Briatore and Arrows owner Tom Walkinshaw refusing to accept the pact. Schumacher had been keen to avoid any accidents at the start, due to a combination of the effects of the 11 September 2001 attacks earlier that week; the death of fire marshal Paolo Gislimberti in a pile-up at the beginning of the previous year's race; and the horrific accident in the previous day's ChampCar race in Germany, in which former Formula One driver Alex Zanardi was critically injured, resulting in the amputation of both legs.
Heidfeld lost hydraulic pressure on the grid; he was required to use the spare Sauber monocoque and start from the pit lane. Fisichella did the same because he had a fuel leak in his car. When the race started, Montoya maintained his pole position advantage going into the first corner, with Barrichello in second and Michael Schumacher in third. Ralf Schumacher passed Michael Schumacher at the Variante Goodyear chicane but Michael challenged Ralf for the position at the exit of Variante della Roggia and got ahead heading into the Curve di Lesmo. Further back, Trulli was hit by Button and was sent into a spin and became the first retirement of the race. Button made a pit stop at the end of the lap for a replacement front wing. Irvine made a good start, rising from thirteenth to seventh by the end of the first lap, while Häkkinen made a poor gateway after going through the chicane to avoid making contact with other drivers and fell to thirteenth. Verstappen made the best start, moving from nineteenth to eighth. At the end of the first lap, Montoya led by half a second from Barrichello, who in turn was followed by Michael Schumacher, Ralf Schumacher, Coulthard, de la Rosa, Irvine, Verstappen, Räikkönen, Alesi, Villeneuve, Bernoldi, Häkkinen, Panis, Frentzen, Alonso, Enge, Heidfeld, Yoong, Fisichella and Button.
Barrichello and Michael Schumacher started to maintain the gap between themselves and Montoya, and started to pull away from Ralf Schumacher. Bernoldi passed Villeneuve for tenth position on lap two, while Irvine dropped to ninth one lap later after he was overtaken by Verstappen and Räikkönen. He later fell behind Alesi, Bernoldi and Villeneuve on the fourth lap. Button's engine failed which caused him to retire on lap five. Irvine lost a further three positions to Häkkinen, Panis and Frentzen one lap later. Coulthard became the third retirement of the Grand Prix after an engine failure on lap seven, which meant Verstappen inherited fifth and Räikkönen moved into sixth. Montoya had a blister on one of his rear tyres which caused him to slide under braking, and was slow exiting the Variante della Roggia chicane which allowed Barrichello to take the lead on the ninth lap. Three laps later, Alesi passed Räikkönen for sixth while Häkkinen moved into tenth after passing Bernoldi on lap 13. Irvine retired on lap 14 because he lost horsepower in his car when a cylinder in his engine stopped working. Verstappen fell to seventh after he was passed by Alesi and Räikkönen on lap 16. Yoong spun at Curva di Lesmo and fell to the back of the field.
Michael Schumacher battled for Montoya for third position until he became the first of the leading drivers to make a scheduled pit stop on lap 18, and rejoined the track in fourth place. The Williams and Ferrari teams were employing different pit stop strategies – the Williams team were planning a one-stop strategy whereas the Ferrari team were planning for two stops. Barrichello (on a lighter fuel load) was able to quickly extend his lead over Montoya to ten seconds by his first pit stop on lap 19. However, Barrichello's pit stop proved problematic: his refuelling rig failed to work which meant he was stationary for around six to seven seconds longer than planned. Barrichello exited the stop in third position, ahead of teammate Michael Schumacher. Häkkinen lost second during the course of the 19th lap, and then lost all gears on the previous lap which forced him to retire. Verstappen retired on the 26th lap because his engine stopped working. At the front of the field, Ralf Schumacher moved into the lead of the race when Montoya made his pit stop on lap 28, where his pit crew made an adjustment to his front wing to rectify an issue Montoya had with oversteer, and he rejoined in third place with a deficit of 5.5 seconds. Frentzen retired from ninth position with a gearbox failure on lap 29. Villeneuve made a pit stop from sixth on lap 34 and retained the position.
Ralf Schumacher opened a gap of 6.1 seconds over Barrichello by his one and only pit stop on lap 35 and rejoined in fourth. de la Rosa was the last one-stop driver to pit on lap 36 from fifth, which he maintained upon rejoining the track. Michael Schumacher made his second pit stop on lap 40, and dropped behind Ralf Schumacher. Montoya moved back into the lead position when Barrichello made a pit stop on lap 41 and rejoined right behind Ralf Schumacher. At the completion of lap 42, with the scheduled pit stops completed, the order was Montoya, Ralf Schumacher, Barrichello, Michael Schumacher, de la Rosa, Villeneuve, Räikkönen, Alesi, Panis, Fisichella, Heidfeld, Bernoldi, Enge, Alonso and Yoong. Further down the field, Enge passed Bernoldi for twelfth on lap 43. Barrichello ran in the slipstream of Ralf Schumacher down the start/finish straight and Schumacher cut the Variante Goodyear chicane after attempting to defend his position, allowing Barrichello to take over second on lap 47. Yoong retired from the race on the same lap after he spun his car into a gravel trap. Bernoldi became the final retirement of the race when his car developed a crankshaft sensor problem on the same lap.
Barrichello closed the gap between himself and Montoya but was unable to catch up to the Colombian who crossed the finish line on lap 53 to clinch his first Formula One victory. in a time of 1'16:58.393 at an average speed of 239.321 kilometres per hour (148.707 mph). Barrichello finished in second position 5.1 seconds behind Montoya, Ralf Schumacher came in third, Michael Schumacher took fourth, de la Rosa took his best result of the season after he finished fifth and Villeneuve rounded out the points-scoring positions in sixth. Räikkönen was the final driver on the lead lap in a close seventh place, and Alesi, Panis, Fisichella, Heidfeld, Enge and Alonso were the last of the classified finishers.
The top three drivers appeared on the podium to collect their trophies and in a later press conference. Montoya said he was "so happy" and "pleased" that he won his first race which was the first for a Colombian driver. He also said that he was not frustrated on not achieving his first victory in the past fourteen races as he was not expecting to win during the season. Barrichello said that he felt that Ferrari put on "a good show" despite his slow pit stop from a fuel rig problem on lap 19. He also believed that his two-stop strategy was the right move and described his weekend as "one of my best". When asked if his car was inconsistent during the Grand Prix, Ralf Schumacher said this was not the case and stated although he had problem with his tyres he felt the Williams finish of first and third was "a great achievement".
Alesi attacked Briatore's role in preventing the drivers from abiding by the pact that was to see no overtaking in the first two chicanes and told the Italian and French media that some team principals threatened their drivers if they did not race. Nevertheless, he was relieved that the race passed without any major incident and said the reason why the majority of the drivers supported Michael Schumacher was that he "behaved like a perfect leader". Villeneuve said to British television station ITV that he felt discussing a no overtaking pact at the race circuit was not the appropriate place: "We are race car drivers, Because we signed contracts before the season and everyone was happy to be a race car driver and to earn millions of dollars. Because we knew a year ago that there would be a race at Monza and nobody complained." FIA president Max Mosley stated that he disagreed with the pact and said that the drivers should have raised the concerns in the months leading up to the Grand Prix.
The result allowed Michael Schumacher to extend his lead in the Drivers' Championship to 50 points over Coulthard. Barrichello's third-place finish allowed him to narrow the gap to Coulthard to be three points behind. Ralf Schumacher remained in fourth position, while Montoya's victory meant he moved into fifth. Ferrari remained in the lead of the Constructors' Championship with an 80-point advantage over McLaren, who's points advantage over Williams had reduced to eight points. Sauber maintained fourth place, while BAR took over fifth position.Bold text indicates the World Champions.
Note: Only the top five positions are included for both sets of standings.