Abstract: The analysis methods of acidolysis hydrocarbon, ultraviolet spectrometry and fluorescence spectrometry are used in soil geochemical exploration for oil-gas in the western margin of Songliao Basin to summarize the geochemical anomaly characteristics of methane, heavy hydrocarbon, aromatic hydrocarbon and its derivatives and altered carbonate, and delineate the Qikeshu grade-Ⅰ composite anomaly and Qianjinmachang grade-Ⅲ composite anomaly. The former is characterized by high anomaly intensity and large scale, with the most favorable oil-gas prospect of Baicheng area as the anomaly area and good oil-gas show in the borehole of ZS1 well, which is the main direction of further exploration, while the latter is in small scale with simple indicator combination but high anomaly intensity, worthy of further attention.