In recent years, with the major breakthrough in oil and gas exploration in the periphery of Sichuan basin, the Yanyuan- Ninglang area has become the key research area for oil and gas investigation of new strata in the new area. The Yanyuan- Ninglang area is located in the western margin of the Yangtze platform. Its complex fault system and frequent tectonic and magmatic activities restrict the generation, transportation and storage of oil and gas in this area. In view of the shallow depth that can be reached by the current oil and gas resources development, this paper first uses the deep structure of the Earth provided by the crash 1.0 library to obtain the regional gravity anomaly in the study area by using the frequency domain interface forward modeling method, and then subtracts the regional gravity anomaly from the surface Bouguer gravity anomaly to obtain the residual gravity anomaly excited by the upper crust. Based on the analysis of the distribution characteristics of regional residual gravity in the Yanyuan- Ninglang and its adjacent areas, they are divided into areas I, II, III and IV on the plane. In combination with the surface geological conditions, the basement fluctuation of zone IV, which is most conducive to the development of oil and gas resources, is inversed by Parker interface inversion, and further divided into 8 sub areas. Based on the comprehensive analysis of the basement fluctuation, gravity profile inversion and magnetotelluric sounding profile inversion in the 8 sub areas, it is considered that the area is a syncline structure in the west of the Kangdian ancient land and in the northeast direction. The anticline structure between the southeast wing of syncline and the Jinhe- Qinghe fault is a favorable exploration structure with good resource potential.