Abstract: A voltage converter capable of adjusting a zero-crossing reference current includes a first power switch, a second power switch, a current sensor circuit, a zero-crossing reference current source, and an adjustment circuit. The first power switch and the second power switch are coupled in series to generate an inductor current. The current sensor circuit is coupled to the second power switch to sense a current flowing through the second power switch and generate a sensing current. The zero-crossing reference current source outputs a zero-crossing reference current. The adjustment circuit is coupled to the current sensor circuit and the zero-crossing reference current source to receive the sensing current and the zero-crossing reference current, so as to control the second power switch and adjust the zero-crossing reference current according to the sensing current and the zero-crossing reference current.