A current balance circuit is used in a multiphase converter, and the multiphase converter includes power stage circuits, the current balance circuit and a control circuit. The current balance circuit includes detection units, a calculation circuit and error amplifiers. Detection units obtain the output power information of their corresponding power stage circuits. After each error amplifier compares the obtained output power information with the average of all output power information, it amplifies differences between the output power information and the average of all output power information and converts the amplified differences to current information, such that the control circuit adjusts currents provided by the power stage circuits according to the current information from the error amplifiers to balance the currents provided by the power stage circuits.