Abstract: In the process of dynamic evolution of collaborative innovation network, what opportunities and constraints do inventors face? We empirically explore the impact of the dynamic of inventors’ ego-networks on their knowledge search depth and breadth and also explore the moderating effect of dynamic of network community on the relationship between the dynamic of ego-network and knowledge search depth and breadth through using negative binomial model based on patents applied by Huawei and Apple companies to USPTO. We found that the ego-network expansion and recession both have an inverted U-shaped influence on knowledge search depth and breadth, and ego-network stability negatively affect knowledge search depth and breadth. Further empirical results show that the expansion of the network community has a positive moderating effect on the inverted U-shaped between the expansion of ego-network and knowledge search depth and breadth, the stability of network community enhances the negative effect of the stability of ego-network on knowledge depth and breadth, and the recession of the network community also has a positive moderating effect on the inverted U-shaped between the recession of ego-network and knowledge search depth and breadth. We try to make up studied on the functional mechanisms of the innovation network from a static perspective and from a single level, and we expect to guide innovator bodies to construct and manage their innovation network.