Abstract: The floral traits and pollination system of Impatiens chinensis were studied. Individual flowers bloom for 2.3 days and the male phase was 6.8 times as long as female phase. The nectar quantity and sugar concentration is 0.56 μL and 28.2%, respectively. Stigma is receptive on the day of anthesis. Pollen viability is highest on the moment of corolla displaying（95%）, thereafter decreases gradually and maintains a considerable level until the flower drops（55%）. The results of P/O detection (5 730.3±2 941.1) and bagging treatments suggest that I. chinensis is self-compatible with facultative xenogamy breeding system, its outcross-pollination require pollinators. I. chinensis is mainly visited by honey-bees, butterflies, bumble-bees and several species in ceratina(Apidae). Bombus trifasciatus is the dominant pollinator. The nectar robber Amegilla caldwelli may be the most important biological factor which influences the sexual reproduction of I. chinensis except for the legitimate visitors.

Key words: Impatiens chinensis, floral traits, pollination system, Bombus trifasciatus, Amegilla caldwelli