A simultaneous estimation algorithm of the sensor gain-phase error and direction of arrival （DOA） is proposed to solve the problem of reduced DOA estimation accuracy due to the sensor gain-phase error. By setting few calibrated array elements on one side of the array， the proposed algorithm changes the structure of the error matrix， according to the characteristics of which it then constructs a transformation matrix. Through the transformation matrix and subspace algorithm， the simultaneous estimation of sensor gain-phase errors and DOA is realized. In addition， the algorithm can solve the problem of inaccurate error estimation when there is a large difference in the source power and achieve a high-precision simultaneous estimation of errors and angles. The experimental simulations demonstrate the correctness and validity of this algorithm.