The utility model discloses a limit device for preventing pulling of bracket rear columns. The limit device comprises a base, a top beam and a shielding beam, wherein four vertical columns support arranged between the top beam and the base to support the top beam and the base, the shielding beam and the base are connected through a front connection rod and a rear connection rod, and limit blocks are arranged at least at one position between the front connection rod and a main reinforcement bar of the base, between the front connection rod and a main reinforcement bar of the shielding beam, between the rear connection rod and the main reinforcement bar of the base and between the rear connection rod and the main reinforcement bar of the shielding beam. Rising height of a bracket is limited by means of the mode of the bracket rising limit blocks, and damage to the bracket vertical columns and connection parts of the bracket vertical columns is avoided completely.