This article analyzes how the core knowledge and competence and their complementarities influence enterprises＇ competitive advantage. We build a model to decide whether and when an enterprise enter into some cooper-ating network. In the conclusion, we argue two points of view. Firstly, enterprises that rely on inheriting the tradition and learning from other organizations as the dominant status to gain the knowledge are apt to enter networks. Otherwise, those enterprises which focus on self-innovation are more inclined to establish the core competence by themselves. Secondly, elastic network organizations will evolve dynamically because of the conflict between learning and innovation faced by enterprises inside networks