The road collapse has been a serious threat for safety of the traffic, and it is of great practical significance to study the detection method of road collapse. This paper analysis the technique and its application of three dimensional ground penetrating radar (GPR) for detecting certain road collapse. In order to find out the spatial distribution characteristics of the road collapse zone, the 23 survey lines are set up in the collapse area by a observed mesh with size of 1.0 m×0.5 m, the data collection are carried out. The observed GPR data are processed by conventional method and the two and three dimensional radar profile were obtained. The comprehensive analysis and explanation of the processed profile are conducted with the geological condition, and the location, depth and development of the collapse are accurately found which proved that the interpretation results are reliable. Engineering practice shows that the application of three dimensional GPR can be rapid, and efficient in road subsidence detection, the detection result can provide key reference for prevention and control of subsidence of subsequent construction and safety.