Abstract: With reference to the request of "specifications for oil & gas geochemical survey" in data processing and anomaly assessment, a software is developed to fully use the visualization technology, spatial analysis and superimposed layers based on Geographical Information System (GIS) and calculation of correlative coefficient of geochemical anomalies, including abnormal strength coefficient, abnormal area coefficient, abnormal background coefficient, abnormal points coefficient and so on for oil and gas geochemical exploration.The software has been successfully applied to Yingge Sea Basin and South Yellow Sea Basin.