Mankjur or Minkajur al-Farghani (Arabic: منكجور الفرغاني) or al-Ushrusani (Arabic: منكجور الأشروسني) was a 9th-century Turkic or Iranian military officer in the service of the Abbasid Caliphate. He was a cousin of the prominent Abbasid general Khaydhar ibn Kawus al-Afshin, thus belonging to the ruling family of Ushrusana. Mankjur accompanied al-Afshin in his campaign against the Khurramite Babak Khorramdin, and was later appointed as governor of Adharbayjan by him in 837. However, in 839, Mankjur, after refusing to give the caliph al-Mu'tasim some of Babak's booty, revolted against him. Al-Mu'tasim responded by sending against him Bugha al-Kabir, who managed to suppress his revolt and imprison him in Samarra. The affair of Mankjur raised suspicions about the loyalty of the al-Afshin, who was accused of encouraging the revolt, and contributed to the general's own downfall in the following year.
Mankjur's nisbah is given variously by the sources as al-Ushrusani or al-Farghani, respectively indicating an origin from the Central Asian provinces of Ushrusana or Farghana. Historian Clifford Edmund Bosworth believed that the first element of Mankjur's name may have been a corruption of the Turkish "ming/bing '1,000' or mengü 'eternal, everlasting,'" and that Mankjur may have been a Turkish slave soldier imported into Farghana prior to entering caliphal service.