Abstract: The molecular differences among Pseudosasa amabilis var. ferrea， Pseudosasa amabilis var. peshuiensis and other Chagan\|bamboo species were identified by analyzing internal transcribed spacer sequence in nrDNA of P.amabilis var. ferrea， P.amabilis var. peshuiensis and other 7 Chagan\|bamboo species. and the phylogenetic tree was established to clarify their taxonomic status. The results showed that ITS length of all tested species ranged from 559 to 648 bp， and their (G+C) content ranged from 46.02% to 57.65%. ITS length of P.amabilis var. ferrea and P.amabilis var. peshuiensis was 559 bp and 614 bp, respectively. Their (G+C) content was 55.64% and 57.65%, respectively. The established phylogenetic tree showed that P.amabilis and its varieties were clustered in one big group， in which P.amabilis var. ferrea and P.amabilis var. peshuiensis were clustered into one small group. The above results indicated that P.amabilis var. ferrea and P.amabilis var. peshuiensis were two variants of Pseudosasa amabilis.

Key words:  Pseudosasa amabilis, ITS, phylogenetic tree