Abstract:By employment of karyological and taxonomic techniques, we determined the karyotype of three species in genus of Silene (Caryophyllaceae) from the Qinghai-Tibet Plateau. The asymmetry index (AI) and polyploidy level were discussed. We made a clustering analysis for karyotype from four species (three species in this study and one species from previous study). The results indicated that: S. dawoensis was diplophyte with a karyotype formula of 2n = 2x = 24 = 20m + 2sm + 2st (asymmetry: 2A, AI: 3.09); S. indica was tetraploid with a karyotype formula of 2n = 4x = 48 = 48m (asymmetry: 1B, AI: 0.88); S. huguettiae was hexaploid with its karyotype formula of 2n = 6x = 72 = 72m (asymmetry: 1A, AI: 0.82). Furthermore, S. dawoensis has the highest value of AI and asymmetry coefficient among three species. Based on results of previous studies, we can speculate that the chromosome numbers of 2n = 24 should be a main character in Silene. The chromosome numbers and karyotype of three species of Silene provided first insights, which supplemented the plant cytological data of Qinghai-Tibet Plateau and cytological classification information for Silene. Taken together, this study will provide basis on illuminating the phylogenetic relationship of Caryophyllaceae in this region.