Abstract: ISSR-PCR was used to detect the genetic diversity and relationship of 41 varieties of Loropetalum chinense var. rubrum. ISSR fingerprinting amplified by 14 ISSR primers revealed a total number of 203 unambiguous bands，of which 148 ones were polymorphic and the polymorphism frequency was 72.9%. As analyzed by NTSYS-pc（version 2.10e），the similarity coefficient between varieties ranged from 0.626 to 0.926. These 41 varieties of L. chinense var. rubrum were divided into five groups by UPGMA based on Jaccard coefficient. Leaf color could be the highest classification trait following with petal shape which reflected the phylogenetic evolution among different cultivars. Additionally，due to the origin and breeding of cultivars，the breeding procedure and the characteristics of parents should be considered in cultivar classification. The inheritance of flower color，leaf shape and habit of branching was not stable，so these traits were not suitable as higher classification standard.

Key words: Loropetalum chinense var. rubrum, ISSR, genetic diversity, genetic relatives