Mut-bisir or Mutu-bisir (fl. 19th century BC) was a senior military official to the Amorite king Shamshi-Adad I. His name appears repeatedly in the Mari letters, and means man of Bishri, referring to the desert region around the Jebel Bishri. In these letters, Anson Rainey describes him as frequently mentioned in connection with troops located near the Euphrates.