Niels Desein (born 9 June 1987) is a Belgian tennis player playing on the ATP Challenger Tour.

4 in the combined junior world rankings in May 2005.

[2] He made his main draw debut on the ATP World Tour at the 2013 Portugal Open as a qualifier.

He represented the Belgium Davis Cup team on one occasion in 2015.

Desein is married to Belgian lawyer Charlotte Verkeyn who was elected as a member of parliament in 2024.