Nine conodont species and forms of the Palmatolepis, Hindeodella, Hibbardella, Polygnathus, and Icriodus genera have been discovered from limestone at Ng«n Kim pass, 6 km northwest of §«ng Khª Townlet, Cao B»ng Province. Among them Palmatolepis triangularis, Pa. delicatula, Pa. clarki belonging to the triangularis Zone, are the most important and characterize the lowermost level of Famennian, Upper Devonian. This conodont discovery affirms the presence of the Upper Devonian in the §«ng Khª area, Cao B»ng Province.