A new species of troglobitic loach,Triplophysa baotianensis sp. nov.,is described based on the specimens collected from a cave (25°24′ 17.16″N,104°44′ 40.37″E),Baotian Town,Pan County,Guizhou Province,China.This new species is the firstly recorded Triplophysa fish distributed in the Nanpanjiang water system.Compared with the five loach (T. nasobarbatula,T. zhenfengensis,T. longliensis,T. longibarbatus and T. jiarongensis) distributed in Guizhou Province,the new species is similar to T. zhenfengensis,but it can be distinguished from T. zhenfengensis by the following characteristics:①the flatted pectoral fin and pelvic fin are cross-shaped with the body (vs. the trend of the pectoral fin and pelvic fin are normal);②the starting point of the dorsal fin is in front of the beginning of the pelvic fin (vs. the starting point of the dorsal fin is after the beginning of the pelvic fin);③the surface of the body is bare (vs. the body is clearly scaly);④the nasal valves develop into a short whisker (vs. the nasal valves are not a short whisker);⑤it is distributed in the Nanpanjiang water system (vs. it is distributed in the Beipanjiang water system).