Abstract: Based on the electromagnetic wave propagation theory and FDTD, forward modeling was carried out to analyze the reflection response characteristics of geological radar, it further showed that GPR was effective in advance detection of coal tunneling. Radar detection of known geological anomalies was carried out in Xinjing Coal Mine, based on the detection results and forward modeling results, 10 GPR reflection characteristics of geological anomalies or phenomena were summarized. As the application test carried out on this basis, the detection accuracy rate of geological anomalies can reach 89%, the application effect of GPR in advance detection of coal tunneling is further improved.