A new species, Dicranum pseudacutifolium Otnyukova is described from North Siberia, Putorana Plateau. It is similar to D. acutifolium and D. brevifolium but differs from both species in the absence of bulgings above cell walls as it is seen on transversal leaf section, in not porose lower leaf cells, and in inner perichaetial leaves abruptly contracted into subula. It differs from D. flexicaule and D. fuscescens in leaf cross section looking like pair of tongs, and from the latter also in relatively scarce rhizoids, and in wide leaf base. A specific feature of this new species is straight cell walls making cell angles sharp, not rounded.