Supported by the National Investigation of Technological Basic Resources Program, we collected seven Myotis specimens (6 males and 1 female) by using mist nets in the Mentougou District of Beijing, as well as in the cities (Shijiazhuang, Tangshan, Chengde, Pingquan, and Zhangjiakou) of Hebei Province during 2023 and 2024. These specimens may represent new distribution records in these regions. We documented their echolocation calls, conducted external morphological and cranial measurements, and performed the phylogenetic analysis based on Cyt b sequences from 20 Myotis species, including M. aurascens (Table 1). The specimens exhibited head-body lengths ranging from 40.6 to 44.9 mm, forearm lengths from 32.6 to 35.0 mm, and body weights from 3.5 to 4.4 g (Table 2). Morphological characteristics included dorsal hairs with buff-colored tips and dark brown bases, ventral hairs with grayish-white tips and brownish-gray bases, slightly rounded pinnae with narrow elongated tragi, long vibrissae, wing membranes attached at the bases of the toes, uropatagia originating from the ankles, and tail tips extending slightly beyond the uropatagium (Fig. 1a). Craniometric analysis identified the maximum skull lengths ranging from 13.7 to 14.2 mm (Table 3), characterized by elongated rostra, a gradual elevation from the posterior rostrum to the frontal region, and a dental formula of 2.1.3.3/3.1.3.3, totaling 38 teeth (Fig. 1b ~ d). The echolocation calls of this species demonstrated a frequency-modulated (FM) pattern with two harmonics, with the highest energy concentrated in the first harmonic (Fig. 2). The peak frequency was measured at 55.1 ± 5.2 kHz (n = 60) for samples from Beijing and 56.8 ± 8.2 kHz (n = 150) for samples from Hebei. Phylogenetic analysis based on partial Cyt b sequences (1 120 bp) revealed that all specimens in this study clustered within the clade of M. aurascens (Fig. 3), exhibiting genetic divergences ranging from 0.002 to 0.014 (Appendix 1), while showing significant divergence from other species of Myotis, with genetic divergence exceeding 0.13 (Appendix 1). An integrated assessment of external morphology, craniodental characteristics, acoustic data, and molecular evidence confirms that the specimens in this study are M. aurascens, representing a novel distribution record for this species in both Beijing and Hebei.