More than 2 600 moss specimens were collected from SinoVietnam border area (Yunnan & Guangxi, China) during 2012 to 2015. Through the specimen identification and literature research, we analyzed the species composition and floristic characteristics of SinoVietnam Border Area (Yunnan & Guangxi, China), comparisons of moss D_Gl and similarity index of genera & species along with floristic spectrum and the cluster analysis of SinoVietnam Border Area (Yunnan & Guangxi, China) with adjacent provinces and countries were made. Results are as follows: (1) the moss flora of SinoVietnam Border Area (Yunnan & Guangxi, China) consist of 452 species (including infraspecific taxa), belonging to 155 genera of 51 families. Taxithelium kerianum (Broth.) Broth. was reported new to China. (2) There are nine dominant families and 12 dominant genera in SinoVietnam Border Area (Yunnan & Guangxi, China). (3) The moss flora of SinoVietnam Border Area (Yunnan & Guangxi, China) is dominated by tropical Asia element, which accounts for 31.19% of the entire species. East Asia element (25.46%) and North Temperate element (13.76%) ranked second and third, respectively. (4)Vietnam has the highest similarity index of genera with SinoVietnam Border Area (Yunnan & Guangxi, China), whereas Guizhou(China) gets the highest similarity index of species within the studied area. (5) The moss flora of SinoVietnam Border Area (Yunnan & Guangxi, China) is more closely related to Guizhou, Guangdong, Fujian and Taiwan.