The invention discloses a tumbler type roller shutter door anti-falling device, which is mainly used for preventing a roller shutter door from falling to hurt people and is simple in structure and safe and reliable in protection. The device mainly comprises an outer cylinder, a torsion spring, a stop arm, an inner cylinder, and a gear rack. The working principle is as follows: in an ascending process of the roller shutter door, the gear rack drives a gear A to rotate and drives the inner cylinder and the stop arm to rotate clockwise by 90 degrees; simultaneously, torsion spring elastic elongation, a long arm of the stop arm is perpendicular to a hinge and is in a stop state; at this time, an electromagnet is energized, the electromagnet and the permanent magnet attract each other; when thedoor curtain continuously ascends and the gear rack on the hinge is separated from the gear A, due to the fact that the electromagnet and the permanent magnet attract each other, the stop arm keeps in a static stop state, no matter what abnormal condition the door curtain occurs, the anti-falling device can prevent the door curtain from falling to hurt people; and when the door curtain of the roller shutter door descends and is close to the anti-falling device, the electromagnet of the anti-falling device is powered off, and the torsion spring retracts elastically and drives the stop arm to reset.