Abstract: Good processing techniques and comprehensive interpretation are mainly used for gravity and magnetic data of offshore oil-gas exploration. In the text, a number of good techniques (comprehensive interpretation for gravity-magnetic and seismic data on profile, multiscale decomposition of wavelet, turning to the pole by all magnetic latitudes variable inclination, 3D forward simulation, geothermal lithosphere bottom inversion) and actual instances of processing and interpretation for gravity and magnetic data on profile and plane are recommended. Gravity and magnetic data are used in oil-gas exploration and studying basic geology. Combination of results and comprehensive interpretation is a short cut to offshore oil-gas exploration.