Denis Gremelmayr (born 16 August 1981) is an inactive German male tennis player.

His career-high singles ranking is World No.

Glemelmayr was born in Heidelberg, Baden-Württemberg.

He reached the semifinals of Estoril, Barcelona and Los Angeles in 2008, losing to Roger Federer, Rafael Nadal and Andy Roddick respectively.

This biographical article relating to German tennis is a stub.