Taking young root tip of in vitro plantlet of 10 species of Clematis as material, chromosome feature analysis and cluster analysis of karyotype resemblance-near coefficient were conducted by using conventional pressed slice method, to discuss the karyotype features and genetic relationship between species. The results suggested that the chromosome number of ‘Jackmanii’was 14, the chromosome number of the other species were 16, and basic number of chromosome was 8. There existed differences of karyotype parameters in 10 species of Clematis, so karyotype datas could provide a base for the classification and genetic relationship identification of Clematis. To make cluster analysis of karyotypies resemblance-near coefficient, when karyotype resemblance-near coefficient(λ) was 0.818 1, 10 species of Clematis could be divided into 3 groups, when λ was 0.893 9, 10 species of Clematis could be divided into 4 groups.