Ground penetrating radar in the detection of thickness, the face of the environment is very complex, there may be many unpredictable factors, to more clear and precise operation, correct and effective application and analysis, as far as possible to reduce data errors, we should focus on the following indicators, including echoes, road dielectric constant, ground location, etc. Therefore, in the process of ground penetrating radar detection, these parameters should be paid close attention to, on the one hand, to improve the efficiency of detection, on the other hand, to improve the accuracy of detection. The following are some details.