Abstract:The realization effect of knowledge complementary is the key to industry-university-research institute (IUR) collaborative innovation. This paper first makes clear the concept of Knowledge Complementarity in the background of industry-university-research institute (IUR) collaborative innovation from a dynamic perspective. Based on the theory of “Ba” and the knowledge dimension division, the Ba's interaction model in the complementary process is constructed, and the interaction of “Ba” is the basic realization method of knowledge complementation. And then, the knowledge complementarity of IUR is divided into two progressive processes: the partial complementarity and the overall complementarity. Through the self-organization theory and the BS model, the internal operational mechanism of the two phases is described respectively, and the dynamic evolution process of the knowledge complementation based on the interaction of “Ba” is comprehensively depicted.