Morrisonodon brentbaatar is an extinct multituberculate mammal from the Upper Jurassic Morrison Formation of North America. M. brentbaatar was described by Robert T. Bakker in 1998, who originally placed it in the genus Ctenacodon. The fossil remains consist of a jaw fragment containing two upper premolars and the sockets corresponding to two molars. The remains were found in the Upper Jurassic Morrison Formation in Wyoming.