Introduce system’s overall function design concept and key technologies. The system is divided into driving module and driven module. According to the depth of calling, the system can also divide into four application modules, and is developed in coordination with Visual Basic 6.0, Visual FoxPro 6.0 and Visual LISP. Each module uses Windows and AutoCAD as executive support system. Under the control of interface program, the module can automatically execute and transmit data. Focus on the program interface design of the driving module. Users can be allowed to arrange and combine five common types of mechanical transmission. 3905 kinds of transmission scheme that is less than five levels can be got. The system can finish total design computation, work capability computation, tolerance database inquiry and drive part drawing drafting automatically and continuously. Mechanical design efficiency can be greatly improved.