Abstract: A plug-type driver assistance device includes an external brake module and an auxiliary control module. The external brake module includes a hydraulic pump and a control valve group, the control valve group includes an inlet valve and an outlet valve, and the hydraulic pump is connected between the inlet valve and the outlet valve. The auxiliary control module includes a receiving unit, a processing unit and an output unit. The processing unit selectively switches to the original vehicle control mode or the assist driving mode. The original vehicle control mode means that the processing unit receives the accelerator pedal signal and controls the output unit to output the accelerator pedal signal. The assist driving mode means that the processing unit receives the surrounding information of the vehicle, and generates an analog pedal signal and an analog braking signal.