PURPOSE: To rapidly and accurately lap print by plating a flexible board printed with a picture pattern on a screen printing base, then further lap printing a picture pattern on a printed board by a next aligned screen printing plate.

CONSTITUTION: Positioning holes are formed at two points on the diagonal lines of boards in which first printing is finished, one of which is used as a dummy. Then, a second screen printing plate 2 is suitably set in a screen printer 20, and a dummy board 5 is adhered with a tape 3 while observing the picture pattern of the plate 2 inside the plate 2. Then, the tape 2 which adheres the board 5 is peeled, and the board 5 is removed from the plate 2. Thereafter, the positioning hole of the board desired to be lap printed is aligned to a marker 7 on a printing base 1 with bare eyes, the board is secured on the base 1, and lap printed. Thus, even if the profile dimensional accuracy of the board is wrong, its alignment accuracy does not become irregular.