Abstract: A jig for a cross hatching test which is rectangular in shape and is used for ruling straight lines intersecting each other at a predetermined angle on a rectangular test plate, including (a) a first straight line passing on the surface of the jig with an angle, for adjusting the left longer side of the test plate to draw a straight line on the test plate with the right longer side of the jig; (b) a second straight line orthogonal to the first straight line, for adjusting the lower shorter side of the test plate; (c) a third straight line with the predetermined angle to the left longer side of the jig, for adjusting the drawn straight line to draw another straight line with the left longer side of the jib with the predetermined angle to the previously drawn straight line; and (d) an opening interposed in the middle of the first straight line, for adjusting the left longer side of the plate to the first straight line to draw the straight line on the test plate with the right longer side of the jig.