A printed wiring board (1) includes: a base substrate (3); a plurality of pads (15a, 17a) for electrical connection that are disposed at one surface side of the base substrate (3) and at a connection end portion (13) to be connected with another electronic component (50); wirings (9, 11) that are connected with the pads (15a, 17a); and engageable parts (28, 29) that are formed at side edge parts of the connection end portion (13) and are to be engaged with engagement parts (58) of the other electronic component (50) in the direction of disconnection. The flexible printed wiring board (1) further includes reinforcement layers (31, 32) that are disposed at the other surface side of the base substrate (3) and at a frontward side with respect to the engageable parts (28, 29) when viewed in the direction of connection with the other electronic component, and that are formed integrally with the wirings (9).