A coordinated control method is presented for drivability worse caused by power interruption and torque fluctuation in the powertrain during the mode transition from motor driving mode to hybrid driving mode for a parallel hybrid electric vehicle(PHEV). Firstly, according to the dynamic analysis of the mode switching process and control targets, the switching process is divided into two phases, that is, before clutch engagement and after clutch engagement. Then, the mode switching control strategy based on disturbance compensation is proposed to eliminate disturbance and realize speed synchronization fastly for the former, in which a disturbance observer is designed to estimate and compensate torque disturbances and model uncertainties during mode transition. To the latter, the torque switching control strategy based on motor compensation is devised to realize smooth switching by introducing the torque delay of the engine and using the motor torque to compensate the torque error of engine. Finally, simulation results show that compared with the traditional control method, the jerk can be decreased by 50.5${%