With Visual C++6.0 as the language, following the traditional waterfall model and the software engineering theory, utilizing the technique of the dialog box, picture synthesis in VC, the writers present the developing of the woven fabric CAD system under the environment of Windows98. The system includes weave designing, yarn simulating, color matching, handling hand sample fabric and the testing effect.The basic methods and effect evaluation have been discussed and developed for the weave designing, yarn appearance simulating and fabric color matching, as well as handling hand sample states the image processing, such as DIB(Device-independent bitmap);meanwhile, the developed system has been tested and run in actual design and textile mill trials. The operated results show that the system runs steadily, efficiently and smart, it can be widely used in yarn and fabric design by using with the merits of convenience, celerity and nicety in shortening the developing periods of product; additionally, it provides in fact a new approach to technical design for textile mills.