Abstract: We present the theory of marine magnetic gradiometer survey and the characteristic of wavelet. Based on the wavelet analysis, a method for detecting high frequency magnetic disturbance from the marine magnetic gradiometer data is put forward. The results of data analysis of the test show that the method is effective in interpreting and detecting the high frequency magnetic disturbances which exist in the marine magnetic gradiometer data, even if the magnetic anomaly is small. This method is useful to improve the capability of magnetic detection in the marine magnetic gradiometer survey.