A new Myotis species is described from Central Vietnam and adjacent area of Laos. The new species resembles smaller specimens of the widespread South Asian Myotis muricola, though differs from it and from other small mouse-eared bats by a set of cranial and external characters. Genetic analyses confirm that the new species is distinct from the other named forms of Asian Myotis. Comparison of sequence diversity in the DNA barcode region of the COI gene among East Asian members of Myotis, highlighted several taxonomic questions related to Asian ‘whiskered bats’, suggesting that common morphological diagnostic traits may be shared by genetically divergent species.