1. College of Geo-exploration Science and Technology, Jilin University, Changchun 130021, China;
2. Intelligence and Information Office of Changchun Public Security Bureau, Changchun 130021, China

In this paper, the gravity space derivative imaging technology is proposed to identify the dip of structure. According to the corresponding relationship between the extreme point distribution of the gravity anomaly level and the dip of the structure, the dip of the faults can be visually displayed, and the calculation is simple. The theoretical single-step and double-step model tests show that the gravity space derivative imaging technology can obtain the dip of faults accurately and stably. Moreover, because this method uses the derivative of upper half space gravity data, the result of model test is much free from noise. The gravity derivative imaging technique is used on gravity anomaly data in Songliao Basin to identify the dip of the fault, and it shows that the northern fault of the basin is northwest-dipping, which indicates that the basin structure is mainly controlled by the subduction of western Pacific Plate, and the fault in the southern part of the basin is vertical, which is related to the southward movement of the Siberian Plate in the later stage.