Altimetry based gravity anomaly has poor resolution and relatively smooth effectiveness,which results in difficulty in obtaining local short-wavelength information.It is necessary to fuse altimetry based gravity anomaly with shipborne based gravity anomaly,which has higher accuracy and contains more short-wavelength information than the altimetry based gravity anomaly,and to study the method of multi-source gravity fusion so as to improve the accuracy of gravity anomaly field.In this paper,a kind of multi-source gravity field fusion method based on wavelet analysis was proposed;the authors designed different fusion strategies for different frequency coefficients and also discussed the differences of the fusion results when they are based on different wavelet functions.The proposed method was applied to the northern margin of the South China Sea.The fusion result contains more accurate short-wavelength anomalies than the altimetry-based gravity anomalies along ship tracks,and it also has more accurate long wavelength characteristics than the ship borne gravity anomalies between shiptracks.