The invention discloses an optimized control method for the halogen lamp input voltage. The optimized control method comprises the steps that S10, battery state parameters are obtained through a sensor and transmitted to an engine control unit; S20, the opening degree of an accelerator pedal is obtained through an accelerator pedal position sensor and transmitted to the engine control unit; S30, on-off state signals of a headlamp are obtained through a headlamp switch, sent to a vehicle body controller and sent to the engine control unit through the vehicle body controller; and S40, the enginecontrol unit is connected with an intelligent electric generator through an LIN bus, and the output voltage of the intelligent electric generator is controlled so that electricity can be supplied toa halogen lamp. According to the optimized control method, through the optimized control logic, engine control unit software is changed, and zero-cost problem solving is achieved; and control maximization of the intelligent electric generator can be achieved, the contribution on vehicle fuel consumption is achieved, the complaint of a driver can also be eliminated, and thus the vehicle overall competitive advantage is improved.