To improve soldering to an end surface electrode by providing a land part with a wide land part exposed from a solder resist and a narrow land part which is exposed from the solder resist and connected to the wide land part, and forming a solder pad part at the wide land part.

A solder resist 4 is printed on the lower surface of a circuit board 1 comprising a land part 3, and on the surface of the land part 4, a wide land part 4a exposed from a solder resist 5 and a narrow land part 4b which is, exposed from the solder resist 5, connected to the wide land part 4a are formed by the solder resist 5. The wide land part 4a is formed near an end surface 1a of the circuit board 1, with a solder pad part 6 formed at the wide land part 4a. Electronic parts such as a resistor and capacitor, etc., are fitted to the circuit board 1 while they are connected to a conductive pattern, constituting an electronic circuit unit 7 comprising a single circuit board 1.