The invention discloses a fall-proof U-shaped foot pin for an iron tower and a use method thereof. The fall-proof U-shaped foot pin for the iron tower comprises a U-shape foot pin and a limiting plate, wherein the U-shape foot pin is arranged on a steel frame of the iron tower, end 1 of an open end of the U-shaped foot pin is fixedly connected with the steel frame, end 2 of the open end of the U-shaped foot pin is connected with the lower portion of the limiting plate, the two ends of the open end of the U-shaped foot pin are vertically arranged, the upper portion of the limiting plate passes through the end 1, and fixedly connected with the steel frame together with the end 1 in close mode, and a limiting groove clamped on the steel frame is formed in the back side of the lower portion of the limiting plate. By using the U-shaped foot pin and the limiting plate, the fall-proof U-shaped foot pin for the iron tower can be conveniently and quickly installed on the steel frame, saves a process of manufacturing holes in the steel frame, and is convenient to assemble and unassembled and maintain. Especially for remolding of a traditional reinforcing steel bar foot pin, an existing installation through hole is used, and then the limiting plate and the U-shaped foot pin can be conveniently and quickly installed on the steel frame of the iron tower, remolding is easy, shinning safety of the traditional iron tower and reliability of the foot pin are greatly improved, remolding cost is low, and the fall-proof U-shaped foot pin for the iron tower further has the advantages of being simple in structure and low in cost.