Abstract: The performance of direction finding of traditional MUltiple SIgnal Classification (MUSIC) method decreases sharply in the presence of sensor mutual coupling. In order to estimate effectively Mutual Coupling Matrix (MCM) of array and Direction Of Arrival (DOA) of incident signals, a cascade estimation method of MCM combined with DOA is proposed. Based on the structural features of MCM, DOA and MCM are decoupled by converting array manifold. By solving a quadratic optimization problem under the linear constraint and utilizing peak search technology to obtain DOA and MCM, the mutual coupling errors can be self-calibrated. The effectiveness and superiority of the proposed algorithm are verified by the computational simulation results.