Abstract: The reliable extinction of grounding fault arc is an important guarantee for the safe operation of the distribution network.In view of the problem that it is difficult for the existing active arc suppression methods to take into account the arc suppression requirements of high-resistance and low-resistance grounding faults at the same time, this paper proposes an adaptive active regulation method of grounding fault considering the influence of line impedance of distribution network. Firstly, the variation law of residual voltage and residual current at the fault point with the grounding resistance and the fault distance is deduced, and the mechanism of voltage arc suppression affected by line impedance is proven. Secondly, by comparing the difference of line characteristic parameters between complete arc suppression and incomplete arc suppression of grounding fault current in the distribution network, it is proposed to convert the difference between the total load current of fault phase and the line current of the connection point of the arc suppression converter into residual voltage compensation at the fault point, to offset the influence of line voltage drop on voltage arc suppression. By analyzing the transfer function and Bode diagram of the control system, it is proven that the control method has strong stability and adaptability to the change of line parameters. Finally, the reliability and feasibility of the proposed arc suppression control strategy are verified by MATLAB/Simulink simulation and RT-LAB hardware-in-loop experiment.