| Donald Nelsen | |
| Birth Date: | 4 September 1944 |
| Birth Place: | St. Louis, United States |
| Height: | 173 cm |
| Weight: | 66 kg |
| Proteam1: | St. Louis Cycling Club, St. Louis |
Donald Nelsen (born September 4, 1944) is a former American cyclist. He competed in the team pursuit at the 1964 Summer Olympics.[1]