| Nicolae Diaconu | |
| Full Name: | Nicolae Virgil Diaconu |
| Nationality: | Romanian |
| Birth Date: | 4 September 1980 |
| Birth Place: | Oradea, Romania |
| Height: | 180 cm |
| Weight: | 88 kg |
| Currentnumber: | 4 |
| Nationalyears1: | 2011-2014 |
Nicolae Virgil Diaconu (born 4 September 1980) is a Romanian water polo player. At the 2012 Summer Olympics, he competed for the Romania men's national water polo team in the men's event. He is 5 ft 11 inches tall.