A method of singlephasetoground faultzonelocation based on measured entropy of zero sequence current is proposed.Based on the detection of the zero sequence current value of each point, by obtaining the sample entropy of each point, the absolute value of the difference between the two points of the sample is obtained,. Finally, by determining the absolute value of the difference Two points correspond to the section to find the fault occurrence section.The simulation model of singlephase earth fault is constructed by using ATP, focusing on the arc suppression coil grounded.Through a large number of ATP experiments,It shows that in different initial phase angle and different ground resistance case, the method can effectively determine the fault location.