A molding process for a thermal insulation component of a refrigerating device provided with a thermal insulation component which comprises an inner insulation foam layer and a seamless stiff polymer material layer formed by reaction injection molding and surrounding the inner insulation foam layer, wherein • the insulation component is a door of a cold storage device or a cabinet, • the seamless stiff polymer material layer is a seamless stiff PU layer, • the seamless stiff polymer material layer has hardness of 75D or more to meet the requirement on the hardness of the insulation component, • the seamless stiff polymer material layer has density and hardness that is greater than the density and hardness of the inner insulation foam layer respectively; and • the inner insulation foam layer is an inner insulation PU foam 1 layer, comprising the following process steps: A. fixing an inner insulation foam layer into a mold; B. injecting into the mold a reaction material to form a seamless stiff polymer material layer surrounding the inner insulation foam layer by reaction injection-molding, wherein step B is a step of injecting PU reaction material into the mold, forming a seamless stiff PU layer surrounding the inner insulation foam layer by reaction injection-molding, wherein • the reaction material is injected through a inlet of the mold until the reaction material fills up the mold, and then reaction curing the reaction material by maintaining the temperature to form a seamless stiff polymer material layer surrounding the inner insulation foam layer, and the temperature maintained for the reaction curing is 45°C to 80°C, and the time for the reaction curing is 1 to 10 minutes, wherein the mold is provided with a heating device and before step B, the mold is pre-heated to 45°C - 80°C; • the viscosity of the reaction material is 100 - 1000 mpa.s,, • the inner insulation foam layer is an inner insulation polyurethane foam layer; the mold is a mold for integrated molding of the seamless stiff polymer material layer; and the reaction material is a polyurethane-synthesizing material for forming the seamless stiff polymer material layer, and • the thermal insulation component is an insulation door or cabinet having a shell and a liner, and the shell and the liner are integratedly formed by the seamless stiff polymer material layer. • the insulation component is a door of a cold storage device or a cabinet, • the seamless stiff polymer material layer is a seamless stiff PU layer, • the seamless stiff polymer material layer has hardness of 75D or more to meet the requirement on the hardness of the insulation component, • the seamless stiff polymer material layer has density and hardness that is greater than the density and hardness of the inner insulation foam layer respectively; and • the inner insulation foam layer is an inner insulation PU foam 1 layer, comprising the following process steps: A. fixing an inner insulation foam layer into a mold; B. injecting into the mold a reaction material to form a seamless stiff polymer material layer surrounding the inner insulation foam layer by reaction injection-molding, wherein step B is a step of injecting PU reaction material into the mold, forming a seamless stiff PU layer surrounding the inner insulation foam layer by reaction injection-molding, wherein A. fixing an inner insulation foam layer into a mold; B. injecting into the mold a reaction material to form a seamless stiff polymer material layer surrounding the inner insulation foam layer by reaction injection-molding, • the reaction material is injected through a inlet of the mold until the reaction material fills up the mold, and then reaction curing the reaction material by maintaining the temperature to form a seamless stiff polymer material layer surrounding the inner insulation foam layer, and the temperature maintained for the reaction curing is 45°C to 80°C, and the time for the reaction curing is 1 to 10 minutes, wherein the mold is provided with a heating device and before step B, the mold is pre-heated to 45°C - 80°C; • the viscosity of the reaction material is 100 - 1000 mpa.s,, • the inner insulation foam layer is an inner insulation polyurethane foam layer; the mold is a mold for integrated molding of the seamless stiff polymer material layer; and the reaction material is a polyurethane-synthesizing material for forming the seamless stiff polymer material layer, and • the thermal insulation component is an insulation door or cabinet having a shell and a liner, and the shell and the liner are integratedly formed by the seamless stiff polymer material layer. • the viscosity of the reaction material is 100 - 1000 mpa.s,, • the inner insulation foam layer is an inner insulation polyurethane foam layer; the mold is a mold for integrated molding of the seamless stiff polymer material layer; and the reaction material is a polyurethane-synthesizing material for forming the seamless stiff polymer material layer, and • the thermal insulation component is an insulation door or cabinet having a shell and a liner, and the shell and the liner are integratedly formed by the seamless stiff polymer material layer.