Late Moscovian–early Gzhelian conodonts occur abundantly in a newly discovered slope section, the Shanglong section, southern Guizhou, South China. The conodont fauna is dominated by P1 elements of Idiognathodus and associated with elements of Swadelina, Streptognathodus and Heckelina. A total of 62 species, including species in open nomenclature, were identified, which are assigned to eight genera. Index conodont species of Middle and Late Pennsylvanian, e.g. I. podolskensis Group, Sw. sp. A, Sw. subexcelsa, Sw. makhlinae, I. heckeli, I. magnificus, I. guizhouensis, H. eudoraensis, I. naraoensis, and H. simulator are all recovered, and their 10 conodont zones are recognized. The richness and abundance of the conodonts throughout the section are analysed. Conodont richness ranges from 1 to 14 and is positively related to conodont abundance (1–379). The composition of conodont elements, i.e. sinistral v. dextral, P1 v. non-P1 and adult v. subadult and juvenile, is presented. The numerical cluster technique is employed to identify four subbiofacies of the slope setting, namely the I. podolskensis, Swadelina, I. swadei–magnificus and Streptognathodus–Heckelina–Idiognathodus subbiofacies.