French Open (Li) Michael Mortensen (born 12 March 1961) is a former professional tennis player from Denmark.

Mortensen achieved a career-high doubles ranking of world No.

Mortensen participated in 22 Davis Cup ties for Denmark from 1979 to 1990, posting an 11–13 record in doubles and a 12–14 record in singles.

He was the captain of the Denmark Fed Cup team in 2011 competing for 2011 Fed Cup Europe/Africa Zone Group I.

1 Li Na, who won the 2011 French Open Women's Singles title under Mortensen.