The utility model discloses an automatic speed limiting structure of a vertical shaft wind-driven generator. The structure comprises a horizontal pull rod of which an inside end is connected with a vertical rotating shaft of the wind-driven generator, and a blade which is arranged in parallel to the vertical rotating shaft, wherein the blade is connected to the outside end of the horizontal pull rod through a rotating shaft which is vertically arranged; a bracket is fixedly connected behind the horizontal pull rod; one end of a tension spring which is arranged in parallel to the horizontal pull rods is connected to a back end of the bracket; and the other end of the tension spring is connected with the blade. By the automatic speed limiting structure of the vertical shaft wind-driven generator, the problems of the conventional manual speed limit and sensor speed limit are solved, and the automatic speed limiting structure of the vertical shaft wind-driven generator has the characteristics that the structure is simple, low in manufacturing cost, high in adaptability and reliability and convenient to maintain and responds sensitively, and real-time automatic speed limit can be realized.