The invention discloses a curvature-adaptive pulley block and belongs to the technical field of mechanical equipment. The curvature-adaptive pulley block comprises two vertical main suspension plates, two transverse support end plates, pulley mounting seats and reinforcing and fixing rods; the vertical main suspension plates are respectively connected with the transverse support end plates through the reinforcing and fixing rods, the vertical main suspension plates are connected with the transverse support end plates, wheel-shape mounting bodies are respectively mounted to two ends of the transverse support end plates and interval insides of the vertical main suspension plates, a pulley is coupled in one end of each pulley mounting seat while a support bar is arranged at the other end of the pulley mounting seat, the support bar is arranged in a hollow connecting rod in each wheel-shape mounting body, a bearing slide column arranged on the support bar is mounted in a sliding rail slot in the hollow connecting rod, and the support bar is further sleeved with a spring. By the arrangement, the problem about curvature fracture of a pulley rope resulting in large damage is solved; the curvature-adaptive pulley block is simple in structure and capable of effectively reducing the curvature of the working rope, and damage due to curvature fatigue is reduced.