Currently, the work of pattern making and fashion sketch drawing is done by designers and pattern makers, respectively. The development of satisfactory garment products requires constant communication between designers and pattern makers. This process is very time-consuming. In this paper, we proposed a body-dimension-based associate design method to integrate fashion sketch drawing and pattern making. First, we accorded dimensions to fashion sketches so that fashion sketches and their corresponding patterns can be associated together by human body dimensions. Then, in the height and width directions, we constructed mathematical models considering fashion sketches, their corresponding patterns and human body dimensions. Finally, a software application based on our proposed method was developed to generate jean fashion sketches and their corresponding patterns, rapidly and automatically. The associated design of fashion sketches and garment patterns in this paper demonstrates the integration of artistic design and engineering design. This novel research idea can be further applied in other design domains.