Abstract: A paddy field with shallow water provides a suitable environment for aquatic animals such as cyprinid fish, which make it possible to develop the rice-fish coculture system. Raising fish in paddy field has a long history in hilly regions of southern China. The rice-fish coculture system has become an important rice farming system in this area, which plays an important role in increasing productivity, stabilizing farmers’ income, and preserving local genetic resources. In this paper, we outlined the development of rice-fish coculture system in southern China, reviewed the recent studies on ecological functions of the rice-fish coculture system (e.g. productivity, pest control and pesticide reduction, soil carbon and fertility maintenance with low fertilizers, methane emission and oxidation, water resource use and the local genetic diversity preservation). The potential and possible approaches for the sustainable development of rice-fish coculture were discussed. The future researches on rice-fish coculture were prospected.