PURPOSE: To enable inspection of positional slippage of an innerlayer conductor pattern by a simple electrical continuity inspecting method wherein the state of continuity between a through hole conductor connected with the innerlayer conductor pattern and a prescribed through hole conductor for inspection of positional slippage out of plurality of through hole conductors for inspection of positional slippage is inspected after an intermediate layer substrate is laminated.

CONSTITUTION: After an intermediate layer substrate 11 is laminated, connection between a through hole conductor 13 of which the outer wall is connected with an innerlayer conductor pattern 12 and a through hole conductor 14-1 for inspection of positional slippage having a clearance of C1, for instance, out of a plurality of through hole conductors 14-1 to 14-5 for inspection of positional slippage having a conductor pattern 15 for inspection of positional slippage around them, is taken. In the case when the continuity between them is ON while the continuity between the through hole conductor 13 and the through hole conductor 14-2 for inspection of positional slippage having a clearance of C2 is OFF, it is determined that the positional slippage of the innerlayer conductor pattern is located within a prescribed length. By this method, the positional slippage of the innerlayer conductor pattern can be inspected easily by a simple electrical continuity inspection without necessitating a troublesome grinding operation.