The invention discloses a control method of a common DC bus open winding permanent magnet synchronous motor system based on two current sensors. The algorithm reconstructs the phase current of that phase without the current sensor through a current observer, further calculates the zero sequence current, and realizes the effective suppression of the zero sequence current. A method for control a permanent magnet synchronous motor system of that invention only adopts the topological structure of two current sensors and a corresponding control method, the speed regulation of the motor and the suppression of the zero sequence current can be realized simultaneously, The control method can reduce the cost of the system by reducing the use of the current sensor, and can also effectively improve the robustness of the traditional three-current sensor system, that is, when a certain sensor fails in the traditional three-current sensor system, the control method of the invention can still make thesystem work normally.