The lithology trap is an important area which can contribute to the petroleum reserve in Jiyang Depression presently. Due to the influence of the limy mudstone，the accuracy of the description of lithology trap is low，which limits its exploration deployment. Based on the XRF microelement measurements of limy mudstone and various methods of micro-analysis such as XRD whole rock mineral analysis，the lithofacies of limy mudstone were divided to solve the geological problem that limy mudstone and sandstone were difficult to distinguish. Through the forward modeling research of seismic reflection characteristics of different lithology combination models，the reflection characteristics of different lithology combinations and their amplitude and frequency differences were determined in the limy mudstone development area. And multi-attribute neural network waveform classification constrained by geological models was established based on multiple seismic attributes analysis and under the guidance of internal seismic reflection structure and external geometry，which can be used to predict the favorable facies belt in the limy mudstone development zone. A new prestack geostatistical inversion method that was constrained by static model was proposed by the application of the method of weighted facies modeling，which can be used to depict the spatial distribution of sandstone reservoir in the limy mudstone development zone. And good exploration result was achieved and proved by drilling.