As one kind of new structure system, long -Span tow-way prestressing ribbed floor-shear wall structure has its remarkable characteristic, and is different with the ordinary ribbed floor structure. This article took an actual project as an example, discussed the design mentality and the design method of this new structure system used in the actual project based upon computation analysis data and existing theory. Moreover, it realized refine reinforcement of ribbed floor by AutoCAD VBA, provided the correlation design mentality for colleagues.