Youssouf Mulumbu joined Norwich City on 22nd June 2015 on a two year contract after he was released by West Bromwich Albion at the end of the 2014/15 season.

The 28 year old combatative midfielder made 211 appearances in six years with Albion, having joined them from Paris St-Germain in 2009, initially on loan. Mulumbu's first term at The Hawthorns was interrupted by injuries and he had to wait until April to make his Premier League debut, coming on as a sub in a 2–2 draw at Portsmouth. He signed for West Brom permanently on a one-year contract for a fee of £175,000 on 10th July 2009

He was a product of PSH's youth team and made 50 appearances for their B team and had a loan spell at Amiens in 2007-09 making 23 appearances, scoring once. He made 13 appearances for PSG.

He was formerly a member of the France under-20 and under-21 teams. He earned his first cap for Congo DR national football team against Algeria on 26th March 2008. In 2009, Mulumbu decided to boycott international football after he claimed his national team lacked professionalism. On 23rd September 2011 he retired from international duties, quoting "numerous problems we were facing with some authorities within the DR Congo Football Federation". However, in July 2012, he decided to revoke this decision, and made himself available for the Congo DR national football team once again.

Injured during pre-season, Mulumbu did not make his Norwich debut until the Capital One Cup clash at Everton on 27th October 2015, which finished 1-1 but the Canaries lost 4-3 on penalties.

On 28th January 2016, Mulumbu was linked by Italian football site, tuttomercarto.web with a loan move to Serie A side Bologna.

He made just 9 appearances for City in 2015/16 as the Canaries were relegated from the Premier League.

On 2nd May 2017, Norwich City announced that they would not be renewing the contracts of seven senior players in the summer including Mulumbu. He had played 15 games in 2016/17 taking his total to 24. He was quickly linked with a move to Derby County.

At the end of June 2017, he was linked with a move to Fulham by African Football magazine whose tweet anout the move he retweeted. The following month saw him linked with Birmingham City. In November 2017, he trained witjh Scottish side Kilmarnock whose new boss Steve Clarke worked with him at West Brom. the Kilmarnock move became reality on 22nd November 2017 with Mulumbu signing until the end of the 2017/18 season.

Mulumbu left Kilmarnock at the end of the 2017/18 season. On 31st August 2018, he signed for Celtic on a two year deal. He made his debut on 23rd September 2018 losing 2-1 against his former club Kilmarnock.

On 31st January 2019, Mulumbu returned to Kilmarnock on loan. He had only played three games for Celtic. He was released by Celtic at the end of the 2018/19 season after the club activated a break clause in his contract.

He rejoined Kilmarnock on 28th August 2020. He left them on 25th May 2021 following their relegation to the Scottish Championship having lost the play-off to Dundee.

On 30th July 2021 he returned to the Congo to join FC Saint Eloi Lupopo