To verify the rationality of networking and the real-time reliability of network transmission for the process level in smart substation, this paper proposes a method of modeling and simulating for smart substation based on OPNET, which models the key network equipments after analyzing the simulation requirement of process level network in smart substation. And several networking modes and optimization strategies for packet transmission are researched. Then the simulation example of Qinyun Substation is used to prove the rationality and effectiveness of the networking strategy, combined with static multicast and different star networks for SV and GOOS E packets, in the practical engineering application. It is certified that the networking strategy meets the applied requirement about the network flow and transmission delay of process level network in smart substation at the moment.