Born in the village of Fissel, in the M'bour Department, Sougou started his career with Dakar-based AS Douanes. He moved to Portugal in 2004 at the age of 19, signing a four-year contract with U.D. Leiria. He made his Primeira Liga debut on 29 November, by coming on as a late substitute in a 1–0 home win against S.L. Benfica.
Sougou continued to compete in the Portuguese top flight in the following six seasons, representing Vitória de Setúbal, Leiria and Académica de Coimbra. In 2009–10, whilst at the service of the latter club, he scored a career-best in the country nine goals in 29 games, helping it to the 11th position; additionally, in early 2013, he revealed that he came close to signing with FC Porto when André Villas-Boas was the manager, but a potential deal fell through due to injury.
In June 2011 Sougou joined Liga I side CFR Cluj, having previously signed a pre-contract agreement. The move was put on hold because his previous club, Académica, wanted €300,000 in compensation, but the transfer was eventually completed whilst the player stated one of the main reasons to sign was rejoining former manager Jorge Costa.
Sougou finished his first year in Romania as joint-ninth top scorer with ten goals, whilst also providing several assists to help his team win the national championship for the third time in five years. In January 2012, chairman Julius Muresan revealed that the player had been given a release clause of €11 million.
On 20 November 2012, Sougou provided two passes for two of teammate Rui Pedro's three goals, in a 3–1 away win over S.C. Braga for the campaign's UEFA Champions League. He himself contributed with two successful strikes in two 2–1 away wins in the qualifying rounds, against FC Slovan Liberec and FC Basel; late in that year, he was named by Gazeta Sporturilor as the second best foreign player in the country behind Wesley Lopes da Silva.
On 24 January 2013, Sougou agreed to a three-year deal with Olympique de Marseille for €4.5 million and a €600.000 annual salary. Upon his arrival, manager Élie Baup stated: "We saw that we were missing an accelerator against Montpellier [...]. Sougou has all of these qualities."
Sougou scored his first goal for the French on 30 January 2013, in a 2–1 success at FC Rouen for the round-of-32 of the Coupe de France. His first appearance in Ligue 1 took place on 3 February, as he featured 13 minutes in a 0–1 home loss to AS Nancy.
Subsequently, Sougou served two consecutive loan spells with fellow league club Evian Thonon Gaillard FC. He was fairly played during his two-year tenure, scoring seven times all competitions comprised and helping his team avoid relegation.
After returning to l'OM, Sougou was left out of the pre-season tour by coach Marcelo Bielsa. He left by mutual consent on 4 August 2015.
On 5 August 2015, Sougou signed for Championship side Sheffield Wednesday on a two-year contract. He scored on his debut for his new team six days later, in a 4–1 win over Mansfield Town for the League Cup at the Hillsborough Stadium.
On 31 January 2017, Sougou returned to Portugal and its top division when he joined Moreirense F.C. until the end of the season and his contract with Sheffield Wednesday. Sougou is currently a free agent following his release.
Sougou made his debut for Senegal on 21 August 2007, playing the first half of a 1–1 friendly draw in Ghana. He was part of the squad that appeared in the 2008 Africa Cup of Nations, playing twice in an eventual group stage exit.
Sougou is a practising Muslim, and observed fasting during the Islamic month of Ramadan.As of 23 May 2015
Liga I: 2011–12