Abstract: An adaptive control method for zero voltage switching belongs to the field of integrated circuit. In the present invention, the difference between the turn-on time of the power tube and the time of the lowest drain voltage of the power tube in the switching cycle is quantified by the reversible counter, and the quantized result is transmitted to the next switching cycle to adjust the turn-on time of the power tube through the final count result of the reversible counter, so that the power tube after being adjusted can be turned on when the drain voltage of the power tube is the lowest, thus reducing the switching loss. The present invention can adaptively turn on the power tube when the drain voltage of the power tube reaches minimum, thus, realizing the zero-voltage switching, reducing the switching loss of the switching power supply, widening the application range.