Adrian Diaconu (born 9 June 1978) is a Romanian former professional boxer who competed from 2001 to 2011, and held the WBC light-heavyweight title from 2008 to 2009. As an amateur he won a silver medal in the middleweight division at the 1999 World Championships and bronze in the light-middleweight division at the 1997 World Championships. Diaconu was born in Ploieşti, Romania, but fought out of Montreal, Quebec, Canada for almost his entire professional career.