Phylogenetic relationships were investigated in the mushroom genus Agrocybe based on sequence data from the internal transcribed spaces(ITS) of nuclear ribosomal DNA(rDNA). Thirty strains including Agrocybe aegerita, A. grocybe cylindracea, A. grocybe praecox, A. grocybe pediades and Unknown Agrocybe species were subjected for the analysis. The Agrocybe spp. were separated into eight distinct groups. Phylogenetic analysis divided these species into eight groups as follows: A. chaxingu within group I, A. salicacola within group II, A. cylindracea and A. aegerita within group III, Agrocybe sp. within group IV and V, and other Agrocybe spp. were grouped within VI, VII, and VIII.