Abstract: It was analyzed and pointed out that distance ranging error caused by non line-of-sight transmission delay of electromagnetic wave was the main reason of reducing mine location precision. For mine target location method based on time of arrival, a non line-of sight error suppression method based on energy detection was proposed. In the method, threshold of direct path and length of signal intercept time are analyzed and counted by testing channel characteristics of coal mine tunnel. In order to identify non line-of-sight signal, arrival time of direct path energy blocks is presented in extracted signal segment by constructing corresponding identification parameters. The experimental testing result shows the method achieves higher range and location precision.