| Marthinus Prinsloo | |
| Office: | 1st President of the Republic of Graaff-Reinet |
| Termstart: | 4 February 1795 |
| Termend: | August 1796 |
| Successor: | Office abolished |
| Predecessor: | Office established |
| Spouse: | Maria Margaretha Klopper |
| Children: | 9 |
| Parents: | Willem Prinsloo de Oude Maria Elizabeth Klopper |
| Birth Date: | 13 February 1751 |
| Birth Place: | Hex River, Dutch Cape Colony |
| Death Date: | 1825 (73-74) |
| Death Place: | Cape Colony |
| Allegiance: | Republic of Swellendam Republic of Graaff-Reinet Voortrekkers |
Marthinus Prinsloo (13 February 1751, Hexrivier – 1825, Cape Colony[1]) was the President of the Republic of Graaff-Reinet from 1795 to 1796 when the British seized the Dutch Cape Colony.[2]
His second cousin, Hermanus Steyn, was President of the Republic of Swellendam in 1795.
He was the father of Hendrik Frederik Prinsloo (1784-1816), who was hanged in 1816 for his involvement in the Slagtersnek Rebellion.[3]