An automatic machine for zig-zag stitching of tubular elements, in particular for stitching trimmings on mocassin type footwear and for fixing transversal reinforcing bands to the vamp of the footwear, where the cylinder containing the "crochet" is circular-sectioned and the work plane on which to lay the material to be stitched is curved with its curve center on the axis of the cylinder and the work plane is supported by a collar co-axial with and external to the cylinder, and longitudinally mobile and rotarily coaxial with respect to said cylinder. The machine also includes the pressure foot which grips the material to be stitched tautly to said work plane, the pressure foot being supported by a guide line fixed to said collar and arranged above the work plane.