An-Nasir Muhammad bin Yusuf (died August 8, 1488) was a contender for the Zaidi state in Yemen, whose term as imam is counted from 1474 to 1488. Muhammad bin Yusuf was a descendant of the imam al-Mahdi Ali (d. 1372) in the fifth generation. When the old imam al-Mutawakkil al-Mutahhar died in Dhamar in 1474, three claimants appeared on the scene. These included Muhammad bin Yusuf, who went from San'a to the mountainous stronghold Thula. From there he made his da'wa (call for the imamate), spreading the message to San'a, Falala and other Zaidi areas. He took the honorific name an-Nasir Muhammad. His two rivals were al-Mansur Muhammad and al-Hadi Izz ad-Din, who belonged to other branches of the Rassids. One Zaidi faction, the Hamzite Sharifs, actually heeded his call and acknowledged him fro