CIRCUIT UNIT HOUSING BOX

It is an object of the present invention to provide a circuit unit accommodation box having a receptacle electrical connector, with the circuit unit accommodation box being able to reliably accommodate a circuit unit comprising a first connector and also allowing the worker to attach the circuit unit to the circuit unit accommodation box with a simple operation when the circuit unit is to be accommodated in the circuit unit accommodation box. The circuit unit accommodation box 1 comprises a box body 10 having at least one circuit unit accommodating part 11 into which a circuit unit 60 equipped with a first connector 71 is inserted, and a receptacle electrical connector 30 that is disposed in the circuit unit accommodating part 11 and that makes an electrical connection with the inserted circuit unit 60. The box body 10 and the circuit unit 60 are equipped with holding means for holding the circuit unit 60 in the box body 10 when the circuit unit 60 is inserted from a first position to a second position.