The present invention relates to a method for manufacturing a medical warmer, and more particularly, in a medical warmer having increased durability so as to be light in weight for easy movement and to prevent deformation of the exterior body due to heat, It relates to the structure of the temperature controller attached to the temperature controller on one side of the outer body to facilitate the temperature control. The composition is as follows. Using a conventional injection machine and ABS resin, a premise of a semi-spherical exterior body formed in a tunnel type, a planar heating element provided on the inner surface of the exterior body, and a medical heater equipped with a temperature controller for controlling the heating temperature of the planar heating element is used. The injection process in which the assembly part is assembled to assemble the temperature controller case on the outer side of the outer body and the outer side of the outer body, the thermal insulation process of attaching the insulator to the inner side of the injected outer body, and the heat transfer to the side of the insulating material are minimized. Aluminum panel attachment process of attaching aluminum panel on one side of planar heating element to make heat generation uniform, and contacting the surface where aluminum panel is attached to insulation material, and then attaching planar heating element to the inside of the exterior body using adhesive cloth When the heating element attaching process and planar heating element attaching process are completed, In order to prevent the gap between the main body and the silicone coating along the gap, and then attach the "a" character (not shown) to the rod attachment process, and the temperature control part on the assembly formed integrally injection molded on one outer surface of the main body In the configuration including a thermostat assembly step of mounting and assembling the thermostat, The assembling unit, to which the temper
