To provide an electronic device capable of simply improving reliability thereof.

An electronic device (1) includes a circuit board (4) having pad portions (26) on which core wire ends (24) of a cable (16) extending from the inside of a casing (12) to the outside of the casing are arranged, wherein joints (28) are formed by soldering the core wire ends to the pad portions in the circuit board. The casing has an opening (14) through which the cable is inserted and a transmission portion (8) provided at a position facing the pad portions and allowing transmission of a laser beam. The joints are formed by laser soldering by means of a laser beam applied through the transmission portion after the circuit board has been housed in the casing.