Based on the Maximum Degree Construction algorithm, a new select algorithm is proposed in this paper. In the algorithm, each node and its neighbors issue the certificates each other to generate the local In-degree and Out-degree certificate repository. Similar to the ant colony algorithm, it finds the certificate chain between the source node and destination node by selecting the node of the maximum certificated times from the beginning. The algorithm reduces the complexity of the selection, provides a guarantee to find the certificate chain, and saves the spending of space as well. Next, this paper gives the simulation of the algorithm and the simulated results show that this is an optimized select algorithm for local certificate repository.