Abstract: For problems that existing coal-rock interface identification methods lacked research on characteristics of coal-rock seam and were unable to interpret data well, a data interpretation method of coal-rock interface detection was proposed combining with coal-rock interface detection model based on ground penetrating radar (GPR). The method uses an improved OTSU to take out threshold segmentation of coal-rock image from GPR under 2D gray histogram, so as to realize coal-rock interface detection. Influence of GPR antenna frequency on detectable coal seam thickness was researched by simulation experiment. The results show that the maximum detectable coal seam thickness in theory would decrease with increase of antenna frequency. Field test was taken out by use of LTD-2100 type GPR with 400 MHz antenna frequency. The test results show that the data interpretation method of coal-rock interface detection based on GPR can improve accuracy of coal-rock interface identification.