Species of Gymnopus sect. Levipedes are challenging to delimitate due to the morphological similarity among different taxa. In this study, morphological characteristics, molecular phylogenetic data, and ecological traits were integrated to investigate the species diversity of this section of southwestern China. A total of 17 species were documented in the region, including three new species, namely G. sinobrevipes, G. flavoalbus, G. yunnanensis, and two species new to the studied area—G. bicolor and G. ocior. Detailed descriptions and illustrations of the three new species are presented, along with comparisons to closely related or morphologically similar species. The remaining species included five that were originally described from southwestern China, four that were first identified from Europe, two from the Republic of Korea, and one from North America. Six of these species, originally described outside of China, currently lack molecular evidence to support their distributions in southwestern China. Finally, 11 species with morphological and molecular evidence were recognized in southwestern China. A key to these species is also provided.