Heyward attended Peachtree Ridge High School in Suwanee, Georgia, where he played for the Peachtree Ridge Lions high school football team. He was the 2006 Georgia Class 5A Defensive Player of the Year. The team tied for the Georgia Class 5A State Championship that same year. He totaled over 100 tackles and 16 sacks as a Senior. He was considered the 7th best football player in Georgia, and the 13th best defensive tackle in the nation by Scout.com. He benched 335 pounds and squatted 510 pounds, and was considered a scholar athlete at Peachtree Ridge High School with a GPA of 3.2.
As a true freshman in 2007, Heyward was named a freshman All-American by Sporting News, Rivals.com and Scout.com after recording 30 tackles, 9 tackles for loss, 2 sacks, and 2 passes broken up. The Ohio State Buckeyes went to the BCS National Championships with Heyward as a freshman, losing to Louisiana State University 38 to 24.
As a sophomore in 2008, he recorded 36 tackles and three sacks. The Buckeyes made it to another bowl game in the 2009 Fiesta Bowl against Texas, losing 24 to 21.
As a junior, in 2009, he had 10 tackles for loss and 6.5 sacks, leading the Ohio State Buckeyes to the Rose Bowl, in which the Buckeyes won 26 to 17 against Oregon. Following his junior season, Heyward decided against declaring for the NFL Draft, instead returning for his senior season with the Buckeyes.
Heyward amassed 48 total tackles and 3.5 sacks in his senior season, returning an interception for a career high 80 yards against Miami. He led the Buckeyes to a berth in the Allstate 2011 Sugar Bowl, beating the Arkansas Razorbacks 31 to 26.
Heyward finished his career at Ohio State with 162 tackles, 31 tackles for loss, 15 sacks, and one interception.
Coming out of Ohio State, Heyward was projected to be selected in the first round by the majority of analysts and scouts. Sports Illustrated ranked him the 16th best prospect and the fifth best defensive end prior to the NFL Combine. Although he attended the NFL Combine, he was only able to perform the vertical after coming off elbow surgery in January. After the combine, he was projected to be selected in the first or second rounds due the high volume of defensive end prospects that were graded highly. At the conclusion of the combine, he was ranked the eighth best defensive end and the 26th best prospect by NFLDraftScout.com. NFL Network analyst Mike Mayock ranked him the seventh best defensive end and 27th best prospect in the 2011 NFL Draft.
Heyward was drafted in the first round of the 2011 NFL Draft (31st overall) by the Pittsburgh Steelers. On July 29, 2011, Heyward signed a four-year $6.70M contract, that included $5.41M guaranteed and a signing bonus of $3.37M.
He entered training camp competing with veterans Brett Kiesel, Aaron Smith, and Ziggy Hood for a starting defensive end position. Going into the regular season, he was named the backup strong side defensive end behind Brett Kiesel. After wearing jersey number 95 during the pre-season of his rookie campaign, Heyward switched to No. 97 after Jason Worilds opted to switch to No. 93.
He made his professional regular season debut in the Pittsburgh Steeler's season-opener against the Baltimore Ravens and made one solo tackle as the Ravens routed the Steelers 35-7. On October 9, 2011, Heyward recorded his first career sack on Tennessee Titan's quarterback Matt Hasselbeck, while also making two solo tackles in a 38-17 victory. During a Week 16 matchup against the St. Louis Rams, he made a season-high three solo tackles in a 27-0 victory.
He finished the season with 11 combined tackles, a sack, a forced fumble, a pass deflection, and he blocked a field goal in 16 games. The Pittsburgh Steelers finished second in the AFC North with a 12-4 record and received a playoff berth.
On January 8, 2012, Heyward appeared in his first career postseason games and made four combined tackles in a 29-23 overtime loss to the Denver Broncos.
He entered training camp competing with Ziggy Hood for the vacant weakside defensive end position. Hood won the job, making Heyward the backup for the season.
He played in the Pittsburgh Steeler's season-opener against the Denver Broncos and made three combined tackles in the 31-19 loss. Th next week, Heyward recorded a solo tackle and made his first sack of the season on Mark Sanchez as the Steelers routed the New York Jets 27-10. On December 30, 2012, he collected a season-high four combined tackles and was credited with half a sack in Thad Lewis during a 24-10 win over the Cleveland Browns. He was used as a rotational defensive end throughout the season and had 20 combined tackles and 1.5 sacks.
Heyward began the regular season as the backup strongside defensive end behind Brett Kissel. He appeared in the Pittsburgh Steeler's season-opener and made one solo tackle in a 16-9 loss to the Tennessee Titans. On September 22, 2013, he earned his first career start in place of weakside defensive end Ziggy Hood and finished the 40-23 loss to the Chicago Bears with one solo tackle. Heyward earned his second start during a Week 6 matchup against the New York Jets and recorded two combined tackles in a 19-6 victory. He remained the starting weakside defensive end for the rest of the season. On November 3, 2013, he made five combined tackles and earned his first sack of the season on Tom Brady, as the New England Patriots routed the Steelers 55-31. In Week 14, he made a season-high ten combined tackles, a sack, and a pass deflection during a 34-28 victory over the Miami Dolphins.
He finished the season with 59 (35). He finished second on the team (first among defensive linemen) with five sacks and led the team with 31 quarterback pressures. He also registered a career-high 59 combined tackles (35 solo), two tackles for a loss, a fumble recovery and seven deflected passes in 13 starts and 16 games.
On April 22, 2014, the Pittsburgh Steelers exercised a fifth-year option on his rookie contract paying him $6.96M in 2015.
Throughout training camp he competed with Brett Keisel, Stephon Tuitt, and Cam Thomas to be a starting defensive end. Defensive coordinator Dick Lebeau named him the starting weak side defensive end, opposite Cam Thomas, to begin the regular season.
He started the Pittsburgh Steelers season-opener against the Cleveland Browns and made four combined tackles and sacked Brian Hoyer in a 30-27 victory. The following game, he recorded a season-high seven combined tackles as the Baltimore Ravens defeated the Steelers 26-6. On October 3, 2014, Heyward was fined $22,050 by the NFL for using abusive language towards an official during Week 4 loss to the Tampa Bay Buccaneers. On December 21, 2014, Heyward recorded four combined tackles and was credited 1.5 sacks on Alex Smith during a 20-12 victory over the Kansas City Chiefs. The following game, he made a season-high six solo tackles, an assisted tackle, and sacked Andy Dalton in a 27-17 win.
He finished the season with 53 combined tackles (33 solo), a career-high 7.5 sacks, and four pass deflections in 16 games and 16 starts. Heyward played in 64 consecutive games during his first four seasons. The Pittsburgh Steelers finished first in the AFC North with a 11-5 record in 2014. On January 3, 2015, Heyward made two combined tackles in a 30-17 loss to the Baltimore Ravens in the AFC Wildcard game.
On July 16, 2015, the Pittsburgh Steelers signed Heyward to a six-year, $59.25M extension that includes $15M guaranteed and a signing bonus of $12M.
Heyward began the season as the de facto left defensive end, along with Stephon Tuitt. He started the season-opener against the New England Patriots and recorded four combined tackles in a 28-21 loss. The next week, he made five solo tackles and sacked Colin Kaepernick as the Steelers routed the San Francisco 49ers 43-18. On November 8, 2015, Heyward racked up a season-high eight combined tackles in a 38-35 victory over the Oakland Raiders.
Heyward finished the season with 54 combined tackles (39 solo), seven sacks, and two pass deflections in 16 games and 16 starts. The Pittsburgh Steelers finished second in the AFC North with a 10-6 record. On January 9, 2016, he made a solo tackle and sacked AJ McCarron during a 18-16 victory over the Cincinnati Bengals. The following game, the Pittsburgh Steelers lost 23-16 to the eventual Super Bowl 50 Champions, the Denver Broncos. Heyward was ranked 88th on the NFL Top 100 Players of 2016.
He started at defensive end in the Pittsburgh Steelers' season-opener against the Washington Redskins and collected two combined tackles in a 38-16 victory. On October 2, 2016, Heyward recorded a season-high seven solo tackles, two pass deflections, and sacked Alex Smith a career-high three times, as the Pittsburgh Steelers routed the Kansas City Chiefs 43-14. During Week 6, he missed the first game of his career with a hamstring injury. His streak ended at 85 consecutive games and 49 consecutive starts.
On November 13, 2016, Heyward suffered a torn pectoral muscle during the Steelers loss to the Dallas Cowboys where he recorded two solo tackles. He announced two days later that he would be placed on injured-reserve and would miss the rest of the season. He finished the season with 22 combined tackles (17 solo), three sacks, and four pass deflections.
Heyward was born in Pittsburgh, Pennsylvania. His late father Craig "Ironhead" Heyward was a former NFL fullback. His father died from cancer, and Cameron was fined by the NFL for uniform violations when he displayed his father's nickname in an eye black message during the NFL's 2015 Breast Cancer Awareness campaign. Cameron stated that being part of the NFL was a blessing and he wanted to honor his dad and raise cancer awareness.
During Heyward's freshman year at Ohio State University, he began dating Allie Schwarzwalder and proposed to her on New Year's Eve 2012 at Savoya. On May 11, 2013, they were married at Westin Convention Center at the Pittsburgh Hotel in Pittsburgh, Pennsylvania.