Abstract: A new species of Gobicricetodon is described from the Middle Miocene of Aya Cave in the Lake Baikal area. It differs from the other species of this genus by its smaller size and some primitive characters of the dentition. In previous studies, Gobicricetodon together withPlesiodipus has been considered as belonging to a distinct Subfamily Gobicricetodontinae. However, great similarities of dentition suggest affinities with several other Eurasian genera grouped in the subfamily Cricetodontinae. To clear up phylogenetic relationships of Gobicricetodonand Plesiodipus with Cricetodontinae, and to enlighten generic and supra-generic systematics of this group, a cladistic analysis using Mesquite 2.72 was done. It reveals three main clades. One of them groupsGobicricetodon and Plesiodipus together with the genera Mixocricetodonand Tsaganocricetus and, surprisingly, with some European species ofCricetodon, including its type species C. sansaniensis. In addition, this analysis suggests an origin for the group from within a Cricetodon-stock of western Eurasia. Another result of this study is that the genusCricetodon is apparently polyphyletic and needs division into several genera.