Abstract: Based on satellites' movement,a number of time slices are divided,during which the network topology can be taken as fixed.On this basis,considering multi-factors like stability,survivability and transmission efficiency and optimizing between them,a clustering algorithm in low earth orbit(LEO) satellite networks are proposed.Applying the algorithm to the Iridium model,simulation results showed that the performances on signaling overhead and scalability were much better than the case of flat network structure.