A temperature control method for a vehicular proton exchange membrane fuel cell system comprises the following steps: detecting a cooling loop inlet temperature of a fuel cell stack by using a temperature sensor, and inputting the temperature into a controller to achieve cooling fan control based on the controller, wherein the cooling fan control comprises fuzzy logic self-adaptive proportional integral control and feedforward compensation control, gain parameters of the proportional integral control are self-adaptively updated by a fuzzy logic algorithm, a load current of the fuel cell serves as disturbance and is used for feedforward compensation, and meanwhile, the opening degree of the fan is determined by the total cooling capacity requirement and the number of cooling fans; and finally, inputting a control signal output by the controller into an actuator of a thermal management subsystem, and conducting cooling inlet temperature control of the fuel cell stack.