The invention provides a steel wire rope overload automatic falling-off lifting sling. The situation that when heavy objects exceed the load carrying capacity of the steel wire rope, the lifting slingcan automatically make the heavy objects be separated is better achieved, and the risk that the heavy objects fall after being lifted is avoided. According to the technical scheme, the steel wire rope overload automatic falling-off lifting sling comprises a clamping device, and the clamping device is composed of two clamping blocks; each clamping block comprises a semicircular arc-shaped block, and horizontal plate clamping devices are connected to the exterior of each clamping block; a first connecting rod and a first pin shaft are arranged below each horizontal plate clamping device, the first connecting rods are arranged on the first pin shafts in a sleeving mode, a strong spring is connected between each first connecting rod and a corresponding baffle, and a supporting frame is internally provided with a limiting step; a second pin shaft is arranged below each clamping device, a sliding block is attached to the inner side of each baffle, and a second connecting rod is hinged to the inner side of each sliding block; transverse through grooves are formed in a bottom plate, and the sliding blocks are located above the transverse through grooves; and adjusting screw rods are fixedto the two sides of a supporting frame, and the end, placed in the supporting frame, of each adjusting screw rod is in threaded connection with a vertical plate. The steel wire rope overload automatic falling-off lifting sling is novel in conception and ingenious in structure.