Distribution patterns of Lasianthus species (Rubiaceae) from East Asia were studied, based on a revision work on the genus and database of collections. Three distribution types of species were recognized as tropical Asian, East Asian and Endemic to China. The type of tropical Asian distribution was further divided into three subtypes as India (Himalayas) to Malesia, India (Himalayas) to Southern China and mainland SE Asia, and Southern China to mainland SE Asia. The species of tropical Asia distribution contribute to 72.7% of the total species, by which the tropical Asian affinity of the flora of southern China is supported. Distributions of some Lasianthus species are well corresponded to the floristic regionalization of Sino-Himalayas and Sino-Japan of East Asian flora, while some distribution patterns indicate a biogeographical connection between Himalayas and Taiwan and a migration pass between Taiwan island and mainland Japan through Ryukyu Islands. The floristic affinities among Chinese continent, Hainan and Taiwan arc also supported by Lasianthus species in the study.