Yusuf IV was the sixteenth Nasrid ruler of Granada in Al-Andalus on the Iberian Peninsula in 1432. He was known as Yusuf Ibn al-Mawl, or in Spanish, Abenalmao. A maternal grandson of Muhammed VI, Yusuf IV was placed on the throne of Granada on 1 January 1432 with the support of the Catholic King John II of Castille, in return for tribute and vassal status. He may be identical to Abenamar in the Romance of Abenamar, a medieval frontier romance describing the meeting with John II.
In 1431, there were several claimants to the throne of Granada. King Muhammed IX had entered Iberia from Tunisia in 1428 or 1429, with the promise of Castilian support in overthrowing Muhammed VIII. However, the Castilian Catholic King John II did not decisively support either, instead playing them against each other to obtain greater tribute and the concession of Granada as a vassal of Castile. Muhammed VIII surrendered in 1429 and was killed in March 1431, leaving Muhammed IX on the throne, but without having reached an agreement with Castile. John II continued to demand greater concessions, and would not offer a permanent peace. Instead, he supported another candidate, Yusuf IV. Yusuf agreed to tribute and to be John's vassal.