The consistency maintenance strategy is the key technology to solve the reliability and consistency of data in the structured peer-to-peer(P2P) network. Based on this technology, the data can be managed at different time and in different regions effectively. However, the spatial heterogeneity, capacity heterogeneity and functional heterogeneity of different nodes pose challenges to data consistency maintenance. Therefore, this paper introduces the basic concept and characteristics of consistency maintenance in the structured P2P network and dissects the challenges and concerned performance metrics in design of the consistency maintenance strategy. According to the proposed classification criteria and system models, the related research work on consistency maintenance strategy are analyzed in depth. Finally, the problems in consistency maintenance strategy design are discussed to point out future research trends and focuses.