Abstract: With the development of the production technique of raschel lace and rapid increase of its market share, the pattern design and development of raschel lace have become very important. After studying the structure of all kinds of raschel lace, aiming at the inadequency in pattern simulation and design speed of the existing CAD system, a bran-new design model for raschel lace CAD system theoretically was offered. A detailed description of lapping movements of guide bars from laying-in, to fall plate through loop forming was made, covering all movements of the guide bars. With this model, raschel lace can be developed visually, rapidly and exactly.