Abstract: As P2.5 plug-in hybrid system with dual clutch transmission boasts high transmission efficiency, no power interruption during gear shifting and mode switching, it shows a wide application prospect. But its mode switching process has significant torque fluctuation due to the difference in torque response characteristics between the engine and the motor, which affects the driving experience. To address the problems, this paper proposes a coordinated control strategy for switching from engine drive to hybrid drive mode, and takes the P2.5 plug-in hybrid system with dual clutch transmission as the research object. On this basis, the actual output torque of the power source is controlled based on the PID feedback principle and the engine torque change rate is limited by controlling the accelerator pedal opening change rate, and the output torque fluctuation is reduced by compensating the engine torque response lag with the advantage of fast drive motor torque response. The simulation model of engine to hybrid drive mode switching based on P2.5 plug-in hybrid system is developed. The simulation results show the maximum shock degree without dynamic coordination control strategy is about 7.1 m/s3 during mode switching, and the maximum shock degree under this strategy is about 1.78 m/s3, down by 74.9%, proving the proposed control strategy can effectively reduce the shock degree during mode switching and improve vehicles’ overall driving stability.