PURPOSE: To enhance rear visibility by locking a mirror in a roughly closed space formed by a housing panel and the inside surface of a spoiler in a state that the mirror is housed in by the housing panel, which allows excess members to be removed, and also allows rain and foreign matters to be hardly stuck on the mirror when no housing is required.

CONSTITUTION: A space 5 is formed in the back side of the wing section 36 of a spoiler 3, a housing 6 is provided within the space 5, and a housing panel 9 is rotatably interposed between a cover 8 for the housing 6 and a car body 1. A mirror 10 is fixed onto one side of the surface of a main body section 9a faced to a back window 2 side in a state that the housing panel 9 is in use. In this case, a roughly closed space is formed by the housing panel 9 and the inside surface of the wing section 36 of the spoiler 3, so that the mirror 10 is disposed within the aforesaid space.