Abu Yaqub Yusuf an-Nasr (Arabic: أَبُو يُوسُف يَعقُوب الناصر, romanized: abū yūsuf ya`qūb an-nāṣr) (died 13 May 1307) was a Marinid ruler of Morocco.

In response to this threat, one of Abu Yaqub's first acts was to reach agreement on a fresh treaty with the Nasrid ruler Muhammad II of Granada, ceding all Marinid possessions in Spain, with the exception of Algeciras, Tarifa, Ronda and Guadix.

While Abu Yaqub was busy against Tlemcen, Sancho IV conspired with the Nasrid sultan Muhammad II of Granada to seize the three remaining Marinid citadels in Spain - Tarifa, Algeciras and Ronda - for themselves.

As part of the deal, Muhammad II handed over to Abu Yaqub four valuable 7th-century copies of the Qur'an, which had been drafted by the Caliph Uthman, which the fleeing Umayyads had brought from Damascus to Cordoba back in the 750s and had since been held by the royal treasury of Granada.

The abandonment of his territories in Spain gave Marinid sultan Abu Yaqub a free hand to pursue a war against the Abdalwadids of Tlemcen in 1295.

The death of the Abdalwadid sultan Othman in 1303 prompted the city to contemplate capitulation, but his successor Abu Zayyan I rallied the resistance and ensured it continued to hold out.

With an eye to relieving the siege, Abdalwadid agents persuaded the new Nasrid sultan Muhammad III of Granada to transport a Marinid pretender, a certain Uthman ibn Abi al-Ula, to Ceuta in 1306.

He was succeeded by his son (or grandson), Abu Thabit Amir as Marinid sultan of Morocco, who opted to abandon the siege of Tlemcen and to confront Uthman in Ceuta.