Al-Wathiq ibn Mutasim (d. 847) was an Abbasid caliph who reigned from 842 until 847. He succeeded his father, al-Mutasim, and showed a similar interest in learning; thus he was a great patron of scholars, as well as artists. He was renowned for his own musical talents, and is reputed to have composed over one-hundred songs.

During his reign, a number of revolts broke out, the largest ones in Syria and Palestine. These revolts were the result of an increasingly large gap between Arab populations and the Turkish armies that had been formed by Wathiq's father, al-Mutasim. The revolts were put down, but antagonism between the two groups continued to widen with the Turkish forces gaining power.

Al-Wathiq died in 847 of high fever, and was succeeded by his brother, al-Mutawakkil