In this paper, a new fault diagnosis method is developed for the fault diagnosis of micro-spacecraft cluster. Based on the theory of wavelet neural network, in order to deal with the problem of failure detection of the leader spacecraft and reconfiguration of spacecraft cluster, a fault diagnosis framework is constructed. Combined with wavelet neural network and neural network, it is concluded the fault diagnosis strategy of spacecraft attitude and fault reconstruction technology of satellite attitude, gives the leader of the spacecraft fault reconstruction scheme, and carries out the simulation and verification. Simulation results show that the fault diagnosis method is effective and fault reconstruction is feasible.