N'Doumbou began his football career at Division 1 Gabonese club AS Sogara's youth team. At the age of 12, N'Doumbou departed the country for France to join local club FC Carpentras in the south of France. He later had a stint at Martigues before joining Marseille on a trial. After having a successful trial, N'Doumbou was offered an aspirant (youth) contract. While in the club's youth academy, he was captain of the Marseille under-17 team that won the 2008–09 Championnat National Under-17 league title. On 18 November 2009, N'Doumbou signed his first professional contract. The contract took effect on 1 July 2011 as the player had to play out the two years left on his élite contract.[3][4] N'Doumbou made his professional debut on 9 January 2010, five days after his 18th birthday, in a Coupe de France match against amateur club Trélissac in a 2–0 victory.[5]
On 10 August 2011, N'Doumbou joined Orléans on a one-year loan.[6] After spending a season for the third tier club, N'Doumbou returned to Marseille where he was incorporated in the Marseille B team who were allowed to play in the fifth tier of French football. On 30 June 2013 N'Doumbou was loaned out once again to Orléans. He returned to the Marseille B and despite being included on the bench for Marseille in August 2016, N'Doumbou signed with Belgian third vision side, FCV Dender EH.[7]
In July 2018, N'Doumbou moved to Bulgarian first division club FC Vereya. N'Doumbou resumed his Chinese nationality and joined Chinese Super League side Shanghai Greenland Shenhua in February 2019.[8] N'Doumbou lifted the CFA Cup with Shanghai Greenland Shenhua on 6 December 2019.[9] After four seasons in Shanghai he would move to another Chinese Super League club in Zhejiang on 17 January 2023.[10]
International career
N'Doumbou played for the Gabon national team, earning his first call-up to the team by former coach Alain Giresse in November 2009.[11] He competed for Gabon at the 2012 Summer Olympics.[12] In February 2019, he renounced his Gabonese citizenship to apply Chinese nationality. Given that N'Doumbou appeared in official matches for Gabon, however, he will not be eligible to represent the China national team.[2]
Personal life
N'Doumbou was born in Port-Gentil to a Gabonese father and a Chinese Hakka mother. His parents met in China where his father was attending school.[13]