During a Chiroptera resource survey conducted in 2023 on the Pamir Plateau of China's Xinjiang Uygur Autonomous Region, two male bat specimens were captured. External morphology examination revealed small-sized individuals characterized by long, narrow ears with straight tragus structures tapering to sharp tips—features diagnostic of the genus Myotis. Echolocation call parameters were as follow: omitted signals exhibited a start frequency of 65.12 ± 2.12 kHz, end frequency of 42.78 ± 1.27 kHz, peak energy frequency of 47.41 ± 1.46 kHz, pulse duration of 2.52 ± 0.26 ms, and inter-pulse interval of 94.01 ± 31.41 ms. Integrated analyses incorporating mitochondrial cytochrome b (Cytb) gene sequencing, (skull) morphological traits, and bio-acoustic data conclusively identified the specimens as the steppe whiskered bat, Myotis aurascens. This discovery constitutes the first documented occurrence of M. aurascens in Xinjiang, thereby expanding the confirmed distribution range of this species in China. Notably, these specimens represent the highest-altitude record for the species at 3,200 m above sea level. Our study provides the inaugural comprehensive description of cranial morphology and echolocation signatures for this species in high-altitude habitats. These findings significantly enhance regional biodiversity inventories and contribute critical baseline data for plateau ecosystem research.