A switching mechanism includes a main body, a rotational body, a swinging member, and a biasing member. The swinging member detaches from the shaft portion against a biasing force of the biasing member by a centrifugal force generated at the swinging member in response to rotation of the rotational body rotating in conjunction with movement of the rotational member, for example, a vehicle door, to switch the state of the switching mechanism to an operation allowed state in a state where the rotational member is operated to rotationally move. The biasing force of the biasing member pushes the swinging member to make contact with the shaft portion and engages with the shaft portion by friction to retain the rotational body in a stopped state to switch the state of the switching mechanism to a movement restrained state in a state where the rotational member is stopped from making rotational movement.