Abstract: The analysis of classical gravity anomaly degree variance model is made according to the new gravity field model-EGM2008, the results show that the traditional gravity anomaly degree variance model can’t exactly describe the spectral sensitivity of disturbing gravity funtions. Based on the Moritz model ,a new high degree variance model-TSD model is presented under two spectral sector, the standard deviations and mean value of results comparison with EGM2008 are respectivelly 0.25,0.0 , .The spectral sensitivity of geoid undulation,gravity anomaly,disturbing gravity,deflection of vertical are computed by using the TSD model.The results show that the spectral sensitivity of gravity anomaly,disturbing gravity and vertical deflections increase largely in medium and low spectra.At the same time,the ratio of both three disturbing gravity functions in high spectra decrease largely.