In order to improve the compensation effect of the arc suppression coil, a new tuning method of arc suppression coil based on the constant zero-sequence voltage amplitude is proposed. In this method, the arc suppression coil and resistor are added in the distribution network neutral point. After replacing the resistor, it adjusts the arc suppression coil inductance value, while observes and measures the size of the neutral point offset voltage rms, to coordinate the further adjustment of the arc suppression coil. When the neutral point offset voltage rms is identical before and after replacing the resistor, simultaneous equations, the sum of the capacitance to ground and the sum of the resistance to ground in the distribution network can be accurately obtained, thus to determine the value of arc suppression coil fully compensated inductor L0. Matlab simulation and theoretical calculation verify that the method can obtain a more precise compensation effect. This method has the advantages of simple operation, high accuracy, good compensation effect, so it can be applied to the areas of arc suppression coil tuning.