| Birth Date: | 11 June 1914 |
| Birth Place: | Desenzano del Garda, Italy |
| Death Date: | 5 February 2005 (aged 90) |
| Death Place: | Desenzano del Garda, Italy |
| Sport: | Swimming, water polo |
| Show-Medals: | yes |
Giacomo Signori (11 June 1914 – 5 February 2005) was an Italian swimmer and water polo player. He won two medals at the 1934 European Aquatics Championships, and at least seven national titles in freestyle swimming events.
As a water polo player, he won three national titles with the Rari Nantes Florentia (1934), Canottieri Olona (1947), and Rari Nantes Camogli (1953) teams. After retiring from competitions, he worked as a swimming coach.