Abstract: The author introduces the basic principle and procedure of wavelet analysis and discusses the applicability of the log signal wavelet analysis in the high-resolution sequence stratigraphic division.The cycles of various orders may be obtained after multi-scale wavelet resolution of log signals.He made the cyclic sequence boundaries of various orders determined by lithofacies in the borehole correspond to the wavelet cycles of log signals and then selected appropriate scales for determining stratigraphic sequences.The results indicate that wavelet transform is very suitable to the division of cyclic sequences of intermediate order and smaller orders.The method has great significance for the improvement of the precision of cyclic sequence division,reservoir evaluation and prediction of the precision.