The fabric drapability is the peformation due to fabric weight to sagging, reflecting the drape degree and drape shape of fabric. This paper design a new method to measure the drapability of mulit-layer fabric by computer image processing technology. It can evaluate the drapability performance and the interaction of fabrics and lining. A test equipment was made. Photos were took in planfprm and side elevation in warp and weft by a digital camera while the sample fabric was overhanging naturally. The datas, like drape coefficient and drape degree, were processed and analysized by AUTO CAD. The paper’s results are that: The drape coefficient and the drape degree of the mulit-layer fabric are between the single-layer fabric’s and single-layer lining’s, and they are closer to the target fabrics.