A method for automatically controlling the charge air temperature of an internal combustion engine, in which a coolant flow upstream of a recooler is distributed as a function of the position of a characteristic diagram-type thermostat valve between a recooler coolant flow and a bypass coolant flow. The temperature of the charge air cooler coolant flow is determined downstream of the recooler by the reunited coolant flows, i.e., the recooler coolant flow and the bypass coolant flow. The charge air temperature is determined by the temperature of the charge air cooler coolant flow. A control deviation of a nominal charge air temperature from an actual charge air temperature is computed, a nominal bypass coolant flow is computed as a correcting variable from the control deviation by means of a charge air temperature controller, a control signal (PWM) for actuating the characteristic diagram-type thermostat valve is determined from the nominal bypass coolant flow by a computing unit, and the position of the characteristic diagram-type thermostat valve (6) is determined by the control signal (PWM).