Since its discovery, the taxonomic status of the only species of Kerivoula (Chiroptera: Vespertilionidae: Kerivoulinae) to be found on Taiwan has been confused. Previous studies have assigned this species to either Kerivoula hardwickii or K. titania, both of which occur on continental SE Asia. This uncertainty supports repeated suggestions in the literature that specimens of K. hardwickii collected and/or sampled across SE Asia are likely to represent multiple cryptic taxa. To address these issues, we combined new and existing data from the genus Kerivoula on Taiwan and continental Asia, and performed diagnostic analyses in steps. First, phylogenetic reconstructions based on mitochondrial and nuclear DNA revealed a well-supported group comprising all taxa currently recognized as K. hardwickii, together with the Taiwanese Kerivoula and Kerivoula kachinensis to the exclusion of all other congeneric species. Second, focusing on all members of this monophyletic clade (i.e., K. hardwickii complex) together with K. titania, we used multivariate statistical methods to separate taxa based on morphometric data. Our results provide strong evidence that among these bats, the Taiwanese Kerivoula is a new species that also occurs on continental Asia, for which we provide a formal description and name. In addition, we show that the subspecies K. hardwickii depressa should be elevated to species status. We discuss our findings and the caveats of this and similar studies.