A dentary fragment containing the last two molars (m2–3) from the Late Cretaceous (Santonian–?Campanian) Bostobe Formation exposed at the locality of Shakh Shakh, northeast Aral Sea region, Kazakhstan, is attributed to a new taxon of Zhelestidae, Zhalmouzia bazhanovi Averianov and Archibald gen. et sp. nov. This specimen is only the second mammal described from Shakh Shakh, the unidentifiable eutherian Beleutinus orlovi Bazhanov, 1972, being the first, and it is only the fifth Mesozoic mammal named from Kazakhstan. Zhalmouzia Averianov and Archibald gen. nov. belongs to the endemic clade of Middle Asian zhelestids (Zhelestinae), better known from the Turonian of Uzbekistan.