A adjusting device for a vehicular mirror directly transmits any forces exerted on the mirror between a base member and a rotating member when the mirror is not being adjusted. This permits a small electric motor to be used that can withstand only comparatively small forces exerted on the mirror while the mirror is being adjusted. The device includes the motor, a cylindrical base, a rotating member and a driven member. The mirror is adjusted when the motor drives the rotating member, and the rotating member is uncoupled from the base member. When the motor rotates the driven member, the rotating member is forced axially apart from the base member as a decoupling element on the rotating member slides up an inclined portion on the driven member. When the motor is not driving the rotating member, the rotating member is uncoupled from the motor and couples to the base member.