A fall protection device includes a frame, a rotation unit, a safety belt, and a braking unit. The rotation unit is rotatably disposed in the frame; the safety belt is wound up on the rotation unit, and adapted to be pulled to drive a rotation of the rotation unit. The braking unit includes a braking plate, a braking block, and a stopper. The braking plate is connected to the rotation unit, rotates with the rotation unit coaxially. The braking block is pivotally connected to the braking plate, and includes a stopping part. The stopping part of the braking block can be spun out by a centrifugal force produced by a rotation of the braking plate, and abuts against the stopper to limit the rotation of the rotation unit. The braking block includes an abutted part. The stopper is disposed in a movement path of the abutted part.