Abstract: A new species of the genus Protocobitis, was discovered in an underground water source (110 m depth) located about 5 km away from the county town of Wuming, Guangxi, China, in May 2006. The new species, Protocobitis polylepis sp. nov., is distinguished from the single congener by the following characteristics: 1) light black pigmentation present vs. no pigmentation; 2) entire body covered with scales except for its head and abdomen vs. rudimentary scales present only along the midline of the body; 3) head length 24.1%-24.8% of SL vs. 19.8-22.1% of SL; 4) body depth 16.2%-16.3% of SL vs. 11.5%-13.0% of SL; 5) Inner rostral barbel length 19.8%-21.0% of head length vs. 9.4%-11.8% of head length; outer rostral barbel length 28.6%-30.2 % of head length vs. 15.3%-21.8% of head length; maxillary barbell length 44.6%-46.0% of head length vs. 22.4%-31.8% of head length.