The invention discloses a winch automatic controlling type three-section folding conveyor. The winch automatic controlling type three-section folding conveyor comprises three conveying arms, a main portal frame and a winch. The winch automatic controlling type three-section folding conveyor is characterized by further comprising a secondary portal frame I, a secondary portal frame II, a hydraulicoil cylinder, a limiting device I, a limiting device II and a steel wire rope, wherein the conveying arms are all of a trapezoidal truss type structure; the secondary portal frame I is hinged with a hinging hole in the big end of the second conveying arm, and the limiting device I is arranged on the hinging hole; the secondary portal frame II is hinged with a hinging hole in the small end of the second conveying arm, and the limiting device II is arranged on the hinging hole; the winch, the hydraulic oil cylinder and the main portal frame are mounted on a ship body. According to the winch automatic controlling type three-section folding conveyor, the conveying arms are long enough and are upwards turned over to be folded, and moreover, the hydraulic oil cylinder is not used, so that the load of a belt is decreased, the cost is reduced, and the mass of the conveying arms is reduced; the problems such as safety accident caused by forwards-shifted weight due to excessively high mass of the conveying arm can be solved, and thus the safety coefficient is increased.