The present invention discloses a control method of microwave oven including three stages: 1. stage for producing functional signal. Producing sinoidal functional signal which can be changed according to the voltage inputted by intercept circuit; 2. stage for judging input voltage. Calculating the above-mentioned functional signal, comparing it with rated voltage value and judging that said input voltage is a low voltage state or a high voltage state; and 3. compensation stage. When the input voltage is a low voltage state, the working time of the relay can be relatively elongated, and when the input voltage is a high voltage state, the working time of the relay can be relatively shortened. |