Nowadays, Enterprise Cluster has already become new fulcrum and important tactics to improve regional competitiveness, which is similar to biological ecosystem, and they have a lot of properties in common. The competition model and co-operation model in Enterprise Cluster are researched and built based on Inter specific Competition Model put forward by Lotka and Volterra in this article. This paper discusses how to deal with the competition and co-operation among enterprises in Enterprise Cluster to perform co-evolution, coexistence, prosperity and development of enterprises in Cluster. At the same time, according to the analysis results, some suggestions are given about how Enterprise Cluster may develop healthily and stably.