The invention discloses an automatic limiting valve device for a boiler. The automatic limiting valve device comprises a coal hopper and vertical columns located on the two sides of the coal hopper. The two sides of the coal hopper are connected with pulleys correspondingly. The pulleys are mounted in vertical tracks of the vertical columns and can slide. An automatic limiting valve is arranged on the upper portions of the vertical columns. A steel wire rope is connected on the coal hopper. A transmission device is arranged on the top of the steel wire rope. The steel wire rope embraces the transmission device. The automatic limiting valve is in circuit connection with the transmission device. A pulley antenna is arranged on the pulley of the vertical column located on the same side with the automatic limiting valve. The steel wire rope upward drives the coal hopper to make lift-up motion under the effect of the transmission device, the pulleys on the two sides of the coal hopper make synchronous motion along the vertical tracks, and when the pulley antenna touches the automatic limiting valve, an electromotor on the transmission device automatically powers off, and the coal hopper stops operating. The structure is simple, using is convenient and flexible, practicability is high, and the effect is significant.