Ousmane Diallo Thiao (born 12 June 2007) is a Spanish footballer who plays as a winger for BVB.

Diallo was born on 12 June 2007 in Las Palmas, Spain. He is of Senegalese descent through his parents. He is a native of Gran Canaria, Spain. He initially played as a goalkeeper while playing football at school. He has regarded Brazil international Neymar as his football idol.^[1]

As a youth player, Diallo joined the youth academy of Spanish side Las Palmas. In 2020, he joined the youth academy of Spanish side Alavés. In 2023, he joined the youth academy of German Bundesliga side BVB. He played in the UEFA Youth League while playing for the club.^[2]

Diallo is a Spain youth international. He has played for the Spain national under-15 football team, Spain national under-16 football team, and Spain national under-17 football team. He made five appearances and scored one goal while playing for the Spain national under-15 football team. He made three appearances and scored zero goals for the Spain national under-16 football team.

Diallo mainly operates as a winger. He can operate as a left-winger or as a right-winger. He has been described as "stands out for his ability to take on opposing defenders and, consequently, create dangerous actions. In addition, he is a great free kick taker and his style is very technical and showy".^[3]