Costică Dafinoiu (born February 6, 1954 in Viziru, Brăila County) is a retired boxer from Romania, who represented his native country at the 1976 Summer Olympics in Montreal, Canada. There he won the bronze medal in the light heavyweight division (– 81 kg) after being defeated in the semifinals by Cuba's eventual silver medalist Sixto Soria.
- 1st round bye
- Defeated Robert Nixon (Guyana) walk-over, boycotted over New Zealand's participation
- Defeated Robert Burgess (Bermuda) 5-0
- Lost to Sixto Soria (Cuba) RSC 1
World amateur championship results
- Lost to Mate Parlov (Yugoslavia) PTS