In the distribution network fault location, the impact of information distortion needs to be to focus on, especially when the short-circuit current is used as the fault information. Considering the distortion or failure of real-time information and other issues, the quick location method of the failure point in distribution network is analyzed. Based on the mathematical model of distribution network fault location, firefly algorithm is applied. According to the characteristics of fault location objective function in distribution network, convergence criterion is proposed, which is suitable for fault location mathematical model.