The invention relates to a high-energy-consumption large-deformation buffer device, and belongs to the field of disaster prevention and mitigation engineering. The high-energy-consumption large-deformation buffer device mainly comprises a shell (1), a shape memory alloy ring (2), sliding grooves (3), fusiform claws (4), a loss layer (5) and a movable rod (6). The whole high-energy-consumption large-deformation buffer device is in a rod column shape. The shell is internally provided with partitions with gaps, wherein the partitions correspond to the sliding grooves in number and evenly separate the sliding grooves from the fusiform claws. The shape memory alloy ring, the sliding grooves, the fusiform claws, the loss layer and the movable rod are sequentially placed outside the partitions from exterior to interior. The high-energy-consumption large-deformation buffer device has the advantages of being high in damping force, large in deformation range, low in hysteresis performance and the like and can be widely applied to the field of disaster prevention and mitigation engineering.