The characteristic of large scale and deep layer on dynamic force of Wenchuan Earthquake occurrence has been recognized. The seismicity before Wenchuan Earthquake of May 12, 2008 has been studied, by using the data from 1977 to May, 2008. The characteristics, such as intersection between big and small circularities, between strips in globe scale, and earthquake activity enhanced in deep layer, are important phenomena before Wenchuan Earthquake. Such characteristics have already been found in the phenomena before Tangshan Earthquake in 1976. The directions of particle movement at intersections between strips, circularities, and strip and circularity are different from each other and are locked to each other. Since particle movement cannot be easy released, it will make stress concentric and become a location of large earthquake occurrence. The characteristic of lock in deep layer is not easy to find by observation at shallower earth surface, that means some difficult to detect precursor on the great earthquake. Since the disaster of a great earthquake is very serious, it should be enhanced to collect and study on information of large scale and deep layer.