Analyzing and handling the inconsistency in requirements is critical to the development of complex software systems. How to solve this problem directly influences the quality of requirements specification, as well as the final software production. Based on a common-recognized management framework of requirements inconsistency, this paper summarizes representative researches on this topic. The main aim is to get a comprehensive understanding of the current techniques and methods of inconsistency management. Finally, the paper also identifies some issues which are still open to further research.