A device for preventing swinging of a hung load, according to the invention comprises movable frames (15) provided on right and left sides, respectively, of a traversing trolley (1) and movable relative to the traversing trolley (1) in a direction of movement of the traversing trolley (1), two sets of guide sheaves (13, 14) for winding up lengths of rope and fixedly provided in the movable frames (15) and spaced apart from each other, and moving means (17) for independently moving the respective movable frames (15) on the traversing trolley (1). The movable frames (15) (guide sheaves) are actuated by the moving means (17) provided on the both sides of the traversing trolley (1) to dampen transverse swinging of a load of the traversing trolley (1), swinging of respective skews or a combined swinging thereof. Accordingly, simplification of the device, readiness of control and an increased freedom with respect to arrangement of the device are attained.