Cimolomyidae is a family of fossil mammala within the extinct order Multituberculata. Representatives are known from the Late Cretaceous of North America and Mongolia, from the late Santonian to their extinction at the end of the Maastrichtian. The family is part of the suborder Cimolodonta. Other than that, their systematic relationships are hard to define. Some authors have placed the taxon within Taeniolabidoidea. Kielan-Jaworowska and Hurum (2001) expressly don't. The family Cimolomyidae was named by Othniel Charles Marsh in 1889. It contains the following genera: