The invention relates to a safety device for shackle frame iron tower high altitude work, which comprises a device body (1), wherein the upper end of the device body is provided with a shackle (round steel) hooking part (G) for hooking an iron tower shackle frame, and the lower part is a hooking hole (K); the shackle hooking part consists of a hook (2) and a t-square shaped locking component (4) which can rotate around a shaft (5) arranged in the middle part of the device body (1) and is fixed with a torsion spring (3); a spring wire (6) with exposed and extending ends is blocked on the device body (1); a spring wire (7) with an exposed and extending upper end is fixed on the t-square shaped locking component and is maintained to abut upon the hook (2) and for locking by the torsional force of the torsion spring, and an inner side arc edge contact line of the hook (2), a contact side line of the t-square shaped locking component (4) and a contact point of a round steel shackle fall over the opening side of a center valgoid hook of the rotating shaft (5) to form hook part self-locking. The safety device is convenient, flexible and safe for use and can be operated by a single hand at a high altitude.