To prevent disconnection of a circuit while performing arrangement of electronic components and through-holes or wiring of an electronic circuit matched with the warp direction of a substrate by defining the warp direction of the substrate, in an endoscope where autoclave sterilization can be performed.

In the substrate for an endoscope used for the endoscope where autoclave sterilization can be performed, when thermal stress occurs in the substrate for an endoscope by heating, at least one region is provided where the stress is reduced and the warp of the substrate for an endoscope is defined in a prescribed direction.