Resource and environmental sciences are basic sciences and hot-spot sciences, it is very important to the research on sustainable development. Based on the discussion of the concept of resources and environment, the subject connotations, discipline missions, characteristics and developmental trends of resources and environmental sciences are analyzed in the paper. The author also discusses the methodology of resources and environmental sciences, including data collecting, model-establishing and prediction et al.In the end, the author pointed out that the work of resources and environment research of Chinese Academy of Sciences will make great contribution to the sustainable development of the eco-environment and economy and society of China.