The studied site is located within an abandoned gas station which had nearly existed for 40 years. The authors used ground penetrating radar and high density resistivity method to detect the petroleum hydrocarbon contamination. At the same time, four monitoring wells were drilled in the gas station and samples of groundwater were analyzed so as to verify the accuracy of the two methods in detecting light non-aqueous phase liquids (LNAPLs) contamination. Comprehensive detection results showed that the source of pollution was the leaking pipes, the diffusion range reached the gas station boundary and the vertical distribution of con-tamination was about 0.5~2.8 m. Ground penetrating radar and high density resistivity method used in the investigation provided an excellent tool for environmental detection, suggesting that they can be applied to the study of similar areas.