A method for shape comparison is presented using shape deformation. Unlike many other approaches to shape similarity which use local characteristics such as curvature, our approach captures global features of the shapes being compared and is less sensitive to uneven noise. The problem is cast into polygon-to-polygon deformation (i.e., homotopic deformation) and a new shape signature is introduced based on deformation.A polygon deformation algorithm is presented which runs in O(nk+n log n) time, where n is the number of vertices in the polygonal shapes and k is an index to indicate how the target shape is convoluted. Experimental results are included to demonstrate the feasibility of our approach.