Abstract: Longpeduncled alder(Alnus cremastogyne)occurs naturally in Shichuan Basin and mountain area around the basin,ranging from 26° to 33°N lat. and from102° to 110°E long. Within its natural range,topography,climatic and edaphic conditions vary greatly. Growth performances,morphological and other characters,such as peduncle length,shape and size of pseudo-strobile,1000 seeds weight,basic density and colour of increment core,bole form and bark type,were investigated for 21 locations,having different environmemt conditions. Significant variations within and among stands were found. Variation components between trees within stands were greater than ones among stands for morphological characters and wood density. Rich phenotypic diversity imply that improvement potential would be attractive. According to the cluster analysis for the 8-trait means of stands(locations),the natural range of longpeduncled alder could be divided into 4 districts.