Abstract: In order to clarify the taxonomic status of several species of mites which are common causative agents of mange in many animal populations， the second internal transcribed spacer (ITS-2) of the rRNA gene was sequenced and compared with the homologous sequences of 6 Sarcoptes isolates， 5 Chorioptes isolates， and 21 sequences of mites retrieved from GenBank. The phylogenetic relationships were reconstructed basing on 32 isolates using UPGMA method. The length of ITS-2 was 361 bp in 6 Sarcoptes isolates. In these six nucleotide sequences， a total of 335 nucleotide positions were conserved， 15 were variable sites， and 9 were parsimony informative sites. Homology analyses indicated that the identity levels of nucleotide of ITS-2 among the 6 isolates ranged from 96.9% to 99.7%. The length of ITS-2 in 5 Choriptes isolates were different (225.232 bp). The conserved sites， variable sites， parsimony informative sites were 184， 44 and 9， respectively. The sequence identity of Chorioptes mites from four kinds of cattle or cow ranged from 92.4% to 97.3%， the one between Chorioptes mite from Giant panda and other 4 isolates ranged from 78.7% to 82.6%. A phylogenetic tree constructed using the UPGMA method indicates that the mites examined in this study are clustered in the second major clade corresponding to their second families. The first clade includes the genus of Sarcoptes and Notoedres， the second clade is comprised of the genus of Chorioptes and Psoroptes. According to the homology analysis and phylogenetic analysis， we support the view that the genus Sarcoptes consists of only one species， and the taxonomic status of Chorioptes isolates from Giant Panda and the Psoroptes isolates from buffalo are still to be verificated furtherly.