Mulenga started his footballing career at age 18 with hometown club Afrisport, before moving to Châteauroux in 2004.

[8] On 31 October 2010, in a match against ADO Den Haag, he tore his right cruciate ligament and was sidelined for the entire 2010–11 season.

[9] On 14 August 2011, Mulenga made his comeback and marked this by turning a 0–2 deficit against De Graafschap into a 2–2 final result after scoring two goals.

[10] In August 2014, Mulenga signed with Turkish club Adana Demirspor,[11] before moving to Chinese football six months later.

In October 2020, he joined Dutch second-tier Eerste Divisie club Go Ahead Eagles as a free agent.

[16] He immediately scored in his debut on 17 October, after coming on as a substitute in the 69th minute against FC Eindhoven, as Go Ahead won 3–0.

The country did however manage to qualify for the 2006 Africa Cup of Nations at the expense of the DR Congo and Mali.

Due to an injury, Mulenga did receive any caps during this tournament, but two years later he was part of the team's starting eleven during the 2008 Africa Cup of Nations, and scored the 2–0 goal in a 3–0 win over Sudan.