Abstract: Targeting at the compatibility of sewing technology in apparel manufacturer,through orthogonal test with L_18(6~1×3~6) repeat and mixed orthogonal array,this paper test the seam smoothness of worsted fabric under different sewing conditions and discussed the influences of each sewing condition on seam smoothness.The result indicated: as to the influence on seam smoothness of worsted fabric of medium weight,the tension of sewing thread >sewing thread>the size of sewing needle>stitch density.