A vibration responsive mechanism having a weight suspension rod pendulum which falls in response to the vibration of a base body. The mechanism comprises a responsive disc secured to said rod normally and coaxially and support balls which contact with and bear against the periphery of the disc, individual set of radial guide races having a biasing means biasing the supporting balls in a centripetal direction and a circular opening through which the responsive disc can pass in a vertical direction and a guide skirt being flared from the inner periphery of a circular opening. This mechanism can be actuated in response not only to horizontal vibration but also to vertical vibration.