Abstract: Aiming at the problem of little drilling data and difficulty in sedimentary facies describing of Cretaceous in south central of Chunguang exploratory area, combined with analysis of core facies and electrofacies, based on waveform classification sedimentary microfacies calibration through well seismic combination, 6 colors were selected to represent 6 kinds of waveforms. By using the seismic waveform classification technique, the plane microfacies distribution characteristics of Lianmuqin formation of Cretaceous system were described accurately. It is believed that the fan delta-lacustrine sedimentary system developed in Lianmuqin formation of Chunguang exploration area in the central and southern part. In the Ch55,Ch118 E and Ch120 E well blocks of the study area, three subaqueous distributary channel sand bodies are developed in the leading edge of the fan delta respectively, which are favorable reservoir sand body development areas.