The Achalinus yunkaiensis was firstly described as a new species in 2019. It is only known to be located in the south-west of Guangdong Province. A snake of Achalinus was collected in Maoershan National Nature Reserve, Guangxi, in August, 2014. The specimen was preserved in 75% ethanol for permanent storage after liver tissues was taken and preserved in 100% ethanol. Genomic DNA was extracted from liver tissue using OMEGA Kit, cytochrome c oxidase subunit I (COI) was targeted and amplified using primers Chmf4 and Chmr4. The sequence length of 615 bp was obtained and deposited in GenBank (MT365525). Bayesian inference (BI) analysis was performed in MrBayes 3.2.2. Based on morphological characteristics (Fig. 1) and molecular phylogenetic relationship of mitochondrial COI gene sequence (Fig. 2), this specimen is identified as A. yunkaiensis, which is a new record in Guangxi. The new discovery extends the geographical distribution of A.yunkaiensis to more than 600 kilometers northward.