With the development of information technology, the information service in our country is changing from knowledge production to knowledge service. Knowledge organization system is to realize data information efficiency and knowledge value-added services, and knowledge resources and knowledge service of big data sharing. Therefore, how to construct the knowledge organization system to provide effective information services is one of the key problems in the application of knowledge organization system at present. This paper describes the knowledge organization system and its application conditions, analyzes the problems and reasons of domestic application of knowledge organization system, and expounds the framework and key solutions of constructing knowledge organization system.