Under the condition that structure safety is guaranteed, it is the basic requirement for design units to perform quota design of structure at present. Therefore, a higher standard should be put forward. In the context of quota design, there are two trends for designers, one is try to satisfy the floor level of design norms consequently to reach the quotas, the other is to conduct local adjustment to meet the demand. Actually on demand of quota design there are still some problems in structure design. Accordingly, this thesis is to explore a design optimization method to solve this problem existing in quota design. Compared with traditional design methods and structure optimization method, this thesis is to introduce OOT(object oriented technology)and apply it to data abstraction disposing with the combination of some concepts like class, object, member function and so on. Based on this, problems will be solved optimizingly through programming Visual C++ and solution results will be processed visually through combining CAD interfacing technology.