Abstract: In this paper,the application of coherency cube technique in the 3D data of Baodian Coal Mine is discussed. Using time slice, we can explore small fault and analyse the geological structure by analysing the similarity of seismic signal between adjacent trace on the seismic cube. By analysing and interpreting the actual data, we may find coherency cube technology is an available fault's interpret method. It can improve the interpretable precision and shorten the exploration period.