According to a method for controlling an internal combustion engine by which the tank ventilation operation and an adjustment of the basic mixture can be carried out simultaneously, the engine is operated with an open tank ventilation valve. A first fuel amount correction value is determined for correction of a basic pilot control value for the amount of injected fuel. The regeneration gas volume flow rate is subsequently varied by a predefined change amount. A second fuel amount correction value is determined for correction of the basic pilot control value. Based on the first and second correction values and the flow rate change amount, a third fuel amount correction value is calculated by which the basic pilot control value would have to be corrected to again regulate the exhaust gas composition with a closed tank ventilation valve. Based on the third correction value the basic pilot control value is corrected.