Yusuf ibn Umar al-Thaqafi (Arabic: يوسف بن عمر الثقفي) was a senior provincial governor for the Umayyad Caliphate.
His policies during his tenure as governor of Iraq in 738–744 deepened the Qays–Yaman rivalry and were one of the main factors in the outbreak of the civil war of the Third Fitna, during which he was executed.
A member of the Thaqif tribe, he was related to the powerful governor of Iraq, al-Hajjaj ibn Yusuf al-Thaqafi, who was a first cousin of his father.
[3] In 738, Caliph Hisham ibn Abd al-Malik (r. 724–743) appointed Yusuf to the governorship of Iraq, replacing the longtime governor, Khalid al-Qasri.
[1] Himself a "fanatical Qaysi", Yusuf was largely responsible for the exacerbation of the Qays–Yaman rivalry and, according to Khalid Yahya Blankinship, "nearly completed the total breakdown in the ability of the two groups to live in peace in the same state".