Abu al-Muẓaffar Yusuf ibn Muhammad al-Muqtafi (Arabic: أبو المظفّر يوسف بن محمد المقتفي; 1124 – 20 December 1170) better known by his regnal name al-Mustanjid bi-llah (Arabic: المستنجد بالله) was the Abbasid caliph in Baghdad from 1160 to 1170.

His full name was Yusuf ibn Muhammad al-Muqtafi and his Kunya was Abu al-Muzaffar.

Awn al-Din's[2] Tenure marked the final decline of the Seljuq influence in the Abbasid court (cf.

Their conqueror, Saladin, though himself an orthodox Muslim, initially didn't proclaim the Sunni faith in the midst of a people still devoted to the tenets and practice of the Shi'a sect.

There is little else to say than that this caliph continued to occupy a more or less independent position, with a vizier and courtly surroundings, and supported by only a small force sufficient for an occasional local campaign.