In large-area soil geochemical survey, different geological units have different geochemical backgrounds, forming multiple backgrounds. Geochemical data from different map sheets exhibit deviation caused by sampling methods or analytical methods. This paper aims at leveling the geochemical data from Duobaoshan area of Heilongjiang Province, dividing different geological units into subareas, making normalization processing for data of different subarea, then calculating anomaly contrast based on sampling sites and acquiring element anomalies. In addition,, specification processing can be made for anomaly contrast, and comprehensive anomaly information can be extracted. The above method can effectively reduce background differences and avoid false anomaly. Finally, many gold orebodies were found in the later exploration by the anomaly inspection of certain comprehensive anomalies, which can prove the effectiveness of this method in extracting abnormal information.