Abstract: The saturation line is an important factor to affect the stability and safety of the tailings dam,it is necessary to detect its location and distribution.As geophysical equipment and tools,ground penetrating radar (GPR) has been applied in the dam detection of saturation line.The paper introduced radar technology into the tailings dam saturation line detection,demonstrated the applicability and feasibility of the technology from radar detection mechanism,radar forward analysis and physical characteristics of the tailings dam saturation line.The article explains the methods and processes for the use of GPR to detect saturation line,and analysis the characteristics of the saturation line radar images from the forward modeling and inversion analysis.The author applied GPR on a specific tailings dam to detect saturation line,and the detection conclusion basically in the same with the drilling detection data.It fully shows that the GPR technology is applicable and reliable in the detection of the tailings dam saturation line.