Abstract: To solve the problem of inaccurate fault ranging result caused by uncertainty of wave speed of traveling wave by use of algorithm of single-end traveling wave fault ranging,the paper proposed a new type of ranging algorithm of single-end traveling wave fault ranging.The new type of fault ranging algorithm bases on wavelet transform and makes use of ranging relations among the secondary reflection of fault point,the reflection of end-to-end bus and the initial traveling wave to eliminate influence of wave speed of traveling wave.The simulation result showed that the new type of fault ranging algorithm has the certain effectiveness and feasibility.