In a junction box containing a printed circuit board with electrodes having first end portions soldered to the printed circuit board, an electrode containing member is secured to the printed circuit board on the side of the first end portions of the electrodes, and the electrodes are U-shaped and contained in the electrode containing member in such a manner that the other end portions thereof are extended in a connector inserting hole formed in the junction box, whereby the electrodes are prevented from being adversely affected by external force when the junction box is engaged with the mating connector.