Abstract: The article discussed a new way of demarcating stratigraphic sequences based on the wavelet transform of well-logging data. After discussing the advantage of wavelet transform in time-frequence analysis, the authors introduced the definition and general steps of wavelet transform. The well-logging data from a well in Luxi, being of the highest resolution and best continuity geologically, are processed through continuous wavelet transform for case study and the information of time-frequence chromatogram about coefficients of wavelet transform is extracted. Based on the above, the geological cycles at different scales can be clearly revealed and the abrupt changing points of different levels in the sedimentary sequence are also detected. Furthermore the authors make classification of the sequence and parasequence of Carboniferous-Permian system in Luxi according to these analyses. All these researches provide a new clew and effective method for the classification of sequence.