The invention discloses a large-dog therapy protecting and fixing device, and relates to the technical field of animal protecting and fixing devices. The large-dog therapy protecting and fixing devicecomprises a supporting plate and a supporting frame formed by beams and longitudinal beams; the beams and the longitudinal beams are fixed on the supporting plate respectively, and a safety protection net is arranged on the periphery of the outer side and the upper end face of the supporting frame; two sliding columns are connected between the beams in a sliding mode, limiting blocks are arrangedbetween all the sliding columns and the longitudinal beams, and square grids are arranged on all the sliding columns; an air sac is arranged at the bottom of the supporting frame, an air blower is connected on the air sac, air pipes are arranged on the left side and the right side of the air sac respectively, air cylinders are connected on all the air pipes, arc clamping sheets are connected on the output ends of all the air cylinders, and one-way valves fixed on the longitudinal beams are also arranged between all the air pipes and the air cylinders. According to the large-dog therapy protecting and fixing device in the technical scheme, the problem that in the process that veterinarians treat large dogs, and are easily harmed by the large dogs is solved, and the large-dog therapy protecting and fixing device can be used for protecting and fixing large-dog animals.