Application of wavelet packet energy spectrum method in feature extraction of magnetic flux leakage (MFL) detection signals is an effective signal processing method used widely. However, sometimes MFL signal characteristics in high frequency section are not obvious, the frequency spectrum change is very fragmented, which results in difficult feature extraction. The improved algorithm integration of wavelet packet energy spectrum and Wigner-Ville transform is a signal analysis algorithm which takes continuous wavelet transform and discrete wavelet transform as basic mathematical tool for matching Wigner-Ville transform. In the process of signal processing, the characteristic values to be extracted is defined as the form of energy spectrum and identification and extraction of the characteristic values are converted to identification and extraction of corresponding signal characteristic energy so as to increase the accuracy of MFL signal characteristics in high frequency section.