One female bat was collected in the Xianfei Cave (26°58′24.93″N, 113° 3′23.03″E, alt. 641 m), Sifang Mountain, Hengdong County, Hunan Province, on July26, 2015. The results of morphological measurements and analysis on mitochondrial Cyt b gene proved that this specimen was David′s Myotis (Myotis davidii). The size of this specimen was small with the measurements as forearm length 34.54 mm, foot longer than half of tibia (Fig. 1); skull length was 13.34 mm (Table 1), dental formula 2.1.3.3/3.1.3.3 = 38 (Fig. 2). Agarose gel electrophoresis of Cyt b PCR products shows a clear bright band near 1 000 bp (Fig. 3). The genetic distance based on 1 140 bp Cyt b from this specimen and other M. davidii populations were inferred using the Neighbor-Joining method (Fig. 4). Molecular phylogenetic analysis shows that M. davidii is monotypic, but with two clades. Populations from Guangdong share the same clade with those from Guangxi, while the populations from Jiangshu, Anhui, Hunan, Chongqing form the other clade. The genetic distance between those populations from Jiangshu and Guangxi is the largest. The specimen is preserved in Vertebrate Specimens Museum of Hunan Normal University.