| Sport: | Water polo |
| Birth Date: | 1 April 1943 |
| Birth Place: | Arnhem, Gelderland, Netherlands |
Adrianus ("Ad") Theodorus Moolhuijzen (born 1 April 1943) is a former water polo player from The Netherlands, who finished in seventh position with the Netherlands men's national water polo team at the 1968 Summer Olympics in Mexico City, Mexico.