The embodiment of the application discloses a power supply converter and a control method thereof. The power supply converter includes a primary circuit, a secondary circuit, a resonance circuit and a driving control circuit. The primary circuit includes a primary switch tube and a voltage regulating circuit. The primary switch tube forms a first bridge arm and a second bridge arm. The secondary circuit includes a secondary switch tube. The primary circuit is connected with the input end of the resonance circuit. The secondary circuit is connected with the output end of the resonance circuit. The input end of the voltage regulating circuit is connected with an input power supply of the power supply converter, and the output end of the voltage regulating circuit is connected with the second bridge arm. The voltage regulating circuit is used for regulating voltages of the second bridge arm during starting of the power supply converter. The driving control circuit is connected with the primary circuit and the secondary circuit, and is used for controlling conduction states of the primary circuit and the secondary circuit. Through the embodiment of the application, impact currents during starting of the power supply converter can be reduced effectively, and the stability during starting of the power supply converter can be improved.