Abstract: As one of the research path of open innovation paradigm, user participation innovation is mainly studies how enterprises cooperation with users in the development of new knowledge or new ideas. With the implementation of national strategies and policies, the mass innovation has become a basic guide of research and practice, and innovative management system enters into the evolution of innovation 2.0, the era of mass innovation democratization. Apple, P & G, Merck, Haier, Tencent, etc., there are more and more organizations use crowd model to solve the toughest research problems of innovation. This article firstly based Web of Knowledge of SSCI database data sources, conduct search crowd innovation related topics. By reading and combing through documents, the article summarizes the origins of crowd innovation, meaning and attribution, then the crowd innovation - the essence of knowledge innovation as the starting point and the core, extending to the knowledge identification, knowledge creation and knowledge transfer, three dimensions to establish the cognitive framework of crowd innovation, and compare the crowd innovation practice between P & G and Haier. This make us have a systematic understanding of the crowd innovation, laying the foundation for further innovation and empirical studies.