Abstract：In accordance with the issue of improving precision of gravitational data processing, the paper presented using cosine transform to study the forward modeling and inversion of gravitational anomaly on density interface and theoretically deduced 2-D and 3-D forward formula for cosine transform spectrum of gravitational anomaly on density interface and inverted formula of interface depth. In order to discuss the inverted precision of the method,the Parker-Oldenberg method and cosine transform method were used separately for inversion of the depth of theoretical model with constant density and single interface and errors correlation was carried out. The maximum error and mean variation between using the Parker-Oldenberg method for inverting the depth of interface and the depth of theoretical model at computational point are 0. 148km and 0. 013km separately,while the maximum error and mean variation by using the cosine transform method are 0. 041km and 0. 003km separately and were reduced by 0. 107km and 0. 010km separately in comparison with the in- verted results by the Parker-Oldenberg method, which illustrates that the inverted precision by cosine transform method are obviously higher than that by the Parker-Oldenberg method, which increased by 3 times or more.
