The utility model discloses a safety device for stacker, it includes stacker frame and terraced roof beam, the ladder roof beam is fixed in one side of stacker frame, just the equidistance interval is provided with a plurality of and steps on the rod on the ladder roof beam, wherein, ladder roof beam external fixation is provided with the safety protection cage, the safety protection cage include a plurality of welded fastening in cage that protect on the ladder roof beam binds round, a plurality of protects cage hoop along direction of height equideparture string space setting, just each protects, and welded fastening has a plurality of roots to protect the cage pole setting between the cage hoop. Above -mentioned a safety device for stacker protects the cage in the terraced roof beam external fixation safety of stacker, and that can effectively guarantee the stacker maintains the operation personal security. Not only simple structure, easily realization, and can improve the work efficiency who maintains the operation personnel.