| Sport: | Water polo |
| Birth Date: | 8 December 1924 |
| Birth Place: | Szolnok, Hungary |
| Death Place: | Szolnok, Hungary |
István Hasznos (8 December 1924 - 7 May 1998) was a Hungarian water polo player who competed in the 1952 Summer Olympics.
Hasznos was part of the Hungarian team which won the gold medal in the 1952 tournament. He played two matches and scored seven goals.