A positioning structure that positions two workpieces (1, 2), characterized by comprising: a plate-like one positioning portion that is provided on one of the workpieces and includes one inverted portion and a protruding portion (10; 14); and a plate-like other positioning portion that is provided on the other workpiece and includes another inverted portion and a receiving portion (21; 22), the one positioning portion and the other positioning portion positioning the one workpiece with respect to the other workpiece, by overlapping an end portion of the one positioning portion face-to-face with an end portion of the other positioning portion, wherein the one inverted portion and the other inverted portion are each such that alignment of the positioning portion of each workpiece is inverted when the one positioning portion is overlapped with the other positioning portion; the protruding portion is arranged on the end portion side of the one positioning portion and is provided protruding toward an overlapping side that is a side on which the one positioning portion overlaps with the other positioning portion; and the receiving portion engages with the protruding portion provided on the one positioning portion when the one positioning portion is overlapped with the other positioning portion wherein the positioning structure further comprises a fixing portion provided on the one positioning portion, wherein the fixing portion is arranged on a far side of the one positioning portion and continuous with the protruding portion, and engages with the end portion of the other positioning portion when the one positioning portion is overlapped with the other positioning portion. a plate-like one positioning portion that is provided on one of the workpieces and includes one inverted portion and a protruding portion (10; 14); and a plate-like other positioning portion that is provided on the other workpiece and includes another inverted portion and a receiving portion (21; 22), the one positioning portion and the other positioning portion positioning the one workpiece with respect to the other workpiece, by overlapping an end portion of the one positioning portion face-to-face with an end portion of the other positioning portion, wherein the one inverted portion and the other inverted portion are each such that alignment of the positioning portion of each workpiece is inverted when the one positioning portion is overlapped with the other positioning portion; the protruding portion is arranged on the end portion side of the one positioning portion and is provided protruding toward an overlapping side that is a side on which the one positioning portion overlaps with the other positioning portion; and the receiving portion engages with the protruding portion provided on the one positioning portion when the one positioning portion is overlapped with the other positioning portion wherein the positioning structure further comprises a fixing portion provided on the one positioning portion, wherein the fixing portion is arranged on a far side of the one positioning portion and continuous with the protruding portion, and engages with the end portion of the other positioning portion when the one positioning portion is overlapped with the other positioning portion.