Raymond Anthony Mercer (born April 4, 1961) is a retired American professional boxer, kickboxer, and mixed martial artist who competed from 1989 to 2009.
Best known for his boxing career, Mercer won a heavyweight gold medal at the 1988 Summer Olympics as an amateur, and later held the WBO heavyweight title from 1991 to 1992 as a professional.
As a mixed martial artist, he scored a notable first-round knockout win over former two-time UFC heavyweight champion Tim Sylvia in 2009.