| Rosemary Marcus | |
| Birth Place: | Rivers State, Nigeria |
| Discipline: | Road and Track |
| Role: | Rider |
| Ridertype: | All rounder |
| Show-Medals: | yes |
Rosemary Marcus is a female Nigerian professional cyclist.[1] She won a gold medal while representing Nigeria in the women's time trial cycling event alongside Happiness Okafor, Glory Odiase, and Gripa Tombrapa at the 2015 All-Africa Games in Congo Brazzaville.[2]