| abstract | The genus Cheyletus Latreille, 1776 is redefined and revised, and a key to its 29 valid species is provided. The holotypes of most valid species were examined. One new species, Cheyletus volgini sp.nov., from the nest of Pteromys volans in the far East, is described and 28 species are synonymised. Fifteen poorly described and rarely reported species, whose types are lost, are considered to be inquirendae. Three species i.e. C. funisciuri (Fain, 1972) comb.nov., C. tanzaniensis (Fain, 1972) comb. nov. and C. kivuensis (Fain, 1972) comb.nov. are transferred from the genus Eucheyletia to Cheyletus, and one species described in Cheyletus is transferred to the genus Cheletophyes, i.e. Cheletophyes venator (Vitzthum, 1920) comb.nov. All species of Cheyletus are predators and most are associated with nests of vertebrates or grain stores; their distribution and habitats are listed. |