The invention discloses a device for preventing a liftable elevator car door from being falsely opened. The device comprises a touch ball, an outer car door and a car body, both the touch ball and theouter car door are fixedly mounted on a wall, a touch device is mounted at the bottom edge of the car body corresponding to the touch ball, the touch ball comprises a shell, a center bearing is mounted in the shell, a center gear shaft is mounted at the end of the center bearing, a spring sleeves the outer side of the center gear shaft, the center gear shaft is connected with two clamping tonguesthrough a horizontal gear cross shaft, the clamping tongues are arranged at the end and the center of the other end of the gear cross shaft, and the gear cross shaft is mounted on the shell through across shaft positioning groove. By the aid of pure mechanical working principles, falsely operating probability is zero, the device is wide in applicability and high in expansibility, and both newlymounting cost and late reformation cost are low.