| Giandomenico Costi | |
| Birth Date: | 10 March 1969 |
| Birth Place: | Sassuolo, Italy |
| Height: | 1.82 m |
| Currentclub: | Carpi (assistant) |
| Position: | Defender |
| Years1: | 1985–1990 |
| Years2: | 1990–1991 |
| Years3: | 1991 |
| Years4: | 1991–1992 |
| Years5: | 1992–1995 |
| Years6: | 1995–1996 |
| Years7: | 1996–1997 |
| Years8: | 1997–1998 |
| Years9: | 1998–1999 |
| Clubs1: | Modena |
| Clubs2: | Milan |
| Clubs3: | Messina |
| Clubs4: | Venezia |
| Clubs5: | Lucchese |
| Clubs6: | Brescia |
| Clubs7: | Siena |
| Clubs8: | Alessandria |
| Clubs9: | Ancona |
| Caps1: | 76 |
| Caps2: | 2 |
| Caps3: | 0 |
| Caps4: | 24 |
| Caps5: | 82 |
| Caps6: | 14 |
| Caps7: | 14 |
| Caps8: | 20 |
| Caps9: | 10 |
| Totalcaps: | 242 |
| Goals1: | 1 |
| Goals2: | 0 |
| Goals3: | 0 |
| Goals4: | 0 |
| Goals5: | 0 |
| Goals6: | 0 |
| Goals7: | 0 |
| Goals8: | 0 |
| Goals9: | 0 |
| Totalgoals: | 1 |
| Manageryears1: | 2010–2011 |
| Managerclubs1: | Carpi (assistant) |
| Manageryears2: | 2011 |
| Managerclubs2: | Carpi (caretaker) |
| Manageryears3: | 2013 |
| Managerclubs3: | Carpi (assistant) |
| Manageryears4: | 2014– |
| Managerclubs4: | Carpi (assistant) |
Giandomenico Costi (born 10 March 1969, in Sassuolo) is a retired Italian professional footballer who played as a defender.
Costi played for several Italian clubs throughout his career; he most notably played 2 games in the Italian Serie A for A.C. Milan during the 1990–91 season.