In order to completely analyze carrying capacity ofriver basin water resource, based on different aspect factors affecting water resource carrying capacity and using system method, a generalized index system relating to water resource assessment of river basin is proposed. The establishment of economy, environment and society indexes and the effects of these indexes on water resource evaluation of river basin are especially analyzed. Using these united indexes to evaluate the relation between development of economy, society,environment and water resource among different areas is discussed for typical areas in upstream, middlestream and downstream of Changjiang River Basin. The result shows that using generalized index system to assess river water resource is a better method to reflect water resource sustainable utilization. 