Cooperative innovation is the most important strategic choicefor enterprises in the knowledgeeconomy. As the critical factor for innovation, the Absorptive Capacity (AC) serves a point of penetration for the researches of cooperative innovation. The present literatures about AC ignore the inter-organizationalrelationships and limit the further exploration of cooperative innovation. The relational dimension is added into the classical concept of AC and enhanced it into the dyadic relationship based AC-Relational Absorptive Capacity (RAC) . Through model and simulation of the innovation process, the critical role of RAC in cooperative innovation is revealed, and further more, the driving and supporting mechanisms for the realization of cooperative innovation are explored. . 20 Refs In Chinese