Born in Kinshasa, Congo DR in 1982, Herita Ilunga moved to France as a child, joining Amiens SC at the age of 13 before moving to Stade Rennais at the age of 17 where he spent three seasons before joining RCD Espanyol in Spain in 2002. He moved back to France in summer of 2003 to join AS Saint-Etienne, making 136 league appearances over a four-year span and then joined Toulouse for a single season in summer 2007. At international level he appeared at the 2004 CAF Africa Cup of Nations. Featured in FIFA World Cup qualifying for both the 2006 and 2010 finals and scored his first full international goal in a FIFA World Cup qualifier against Egypt in Cairo on 1 September 2008.

Ilunga, who has played in both the UEFA Champions League and UEFA Cup signed for West Ham United on a season-long loan from Toulouse on 2 September 2008 with the option of a permanent transfer. Ilunga made his Premier League debut in 3-2 defeat at West Bromwich Albion on 13 September 2008, and an ever-present to the season’s end, making 35 appearances and scored his first goal on 3 January 2009 against Barnsley in an FA Cup-tie at Upton Park. Although a series of injuries slowed the African during his second campaign with the Hammers, there is no doubting Ilunga's pedigree.

The Congo DR international turned his loan move into a permanent four-year contract in summer 2009. The DR Congo international then suffered a jaw injury in the 2-0 opening-day victory at Wolverhampton Wanderers on 15 August 2009 and had the second half of the season affected by a long-standing back problem.

Returning from injury he found his playing opportunities limited under new manager Avram Grant. He made only 12 appearances during season 2010/11 and by January 2011 he had been omitted from the first team squad. Following West Ham’s relegation to the Football Championship, the resigning of George McCartney for a second spell, and another change of manager, Ilunga was allowed to join fellow npower championship side Doncaster Rovers, the left-back moved to the Keepmoat Stadium on an emergency loan, having not played for the Hammers since in the Football League Cup first round on 24 August.

On 27 January 2012, Sam Allardyce agreed with Ilunga to terminate his contract with immediate effect. He made 73 appearances in all competitions scoring three goals.

Ilunga resigned for Rovers on an initial one-month contract before returning to France for trails with Guingamp and Brest. On 23 January 2013, Ilunga signs for Rennes. The Congolese footballer later played for French sides Carquefou and Creteil before retiring from the game in 2016.