The numetrical representation of yarn structure of reinforcing material has become a precondition in designing architecture and predicting properties of 3D woven composites. The numetrical representation of topological architecture of woven is discussed in this paper. Yarns are sub-classified and according to the warp yarns fabric directions. A key control point method was proposed to solve the descriptive issue of arbitrary 3D woven composite architecture . In the end, the contrastive tests are done to verify the method.