Diabé Ousmane Cothy Bolumbu Sombo (born 12 July 2004) is a French professional footballer who plays as a left-back for Ligue 3 club Caen.
On 31 May 2022, Bolumbu signed an "elite" contract with Caen, tying him to the club until 2027. This deal meant that he would be under an academy contract for the following two years and under a professional contract the remaining three.
Bolumbu is a France youth international. He was a part of the under-18 squad that won the 2022 Mediterranean Games. On 31 August 2023, he received a call-up to the under-20s for two matches against Denmark.
Born in France, Bolumbu is of Senegalese descent through his father and Congolese descent through his mother.
Coupe Gambardella runner-up: 2021–22