To arrange a joint connector at an optimum location even in a region immersed in water, and to reduce the number of parts and operation man-hour by removing a male connector in the joint connector.

While arranging a waterproof case 10 that is integrally formed of a cover body 11 into which a joint connector 20 is inserted to be housed in the inserted state, and a lid 12 which is attached to the end of an opening end of the cover body 11 via a thin hinge 13 to open and close the opening, the joint connector 20 is composed of a female connector. A plurality of tabs 32 are fitted in the female terminals 40 connected to a plurality of wire ends by inserting joint bus bars 30 projecting a plurality of tabs 32 from a band-shaped coupling part 31 to the insertion holes 23 formed on the female connector. When the joint connector 20 is inserted and locked to the cover body 11, the band-shaped coupling part 31 of the joint bus bars 30 exposed to the housing external surface of the joint connector 20 is fixed in contact with the inner surface of the cover body 11.