One specimen (CH5) was trapped at Hengdaohezi region (44°48′44″N, 129°02′04″E, altitude 740 m) in 2014 in Heilongjiang Province, China. Two more specimens (DE7, DE12) were trapped in 2015 in Dalai Lake region (48°37′20″N, 117°53′17″E, altitude 720 m) in Inner Mongolia Autonomous, China. The three specimens (CH5, DE7, DE12) were identified as Sorex minutissimus (Table 1 and Fig. 1). Two specimens (080910, 090920) that was collected in Laoning Province and recognized as Insectivora, Soricidae were corrected as S. minutissimus (Table 1 and Fig. 2) by the phylogenetic tree constructed by the complete sequence of mitochondrial cytochrome b gene. The specimens (CH5, DE7, DE12) and specimens (080910, 090920) were gathered together in the branch of S. minutissimus (Fig. 3). The result supported morphology results further in this study. The specimens (DE7, DE12) of S. minutissimus are considered as a new record in the mammalian fauna of Inner Mongolia Autonomous. The specimens (080910, 090920) are corrected as the new record of S. minutissimus to the mammalian fauna of Liaoning Province, too.