Begonia longifolia is a species of flowering plant in the family Begoniaceae. It is native to the eastern Himalayas, southern China, Hainan, Taiwan, mainland Southeast Asia, and some of the islands of Indonesia. An erect perennial herb reaching 1.5 m (5 ft), it is typically found in shady, moist forests at elevations from 200 to 2,200 m. It is the most widespread species of Begonia in Asia, and probably in the world.