A method for manufacturing a polyurethane concrete sandwich component comprising a first surface layer, a second surface layer and a polyurethane sandwich layer, wherein the first surface layer and the second surface layer are respectively located on two surfaces of the polyurethane sandwich layer, and at least one of the first surface layer and the second surface layer is a concrete layer, and wherein said method comprises the following steps: i) forming the first surface layer and the second surface layer in molds, wherein the first surface layer and the second surface layer are arranged opposite to each other, and the opposite faces of the first surface layer and the second surface layer are arranged spaced apart from each other, i.e., forming a cavity; ii) making the two surface layers arranged opposite to each other in the molds obtained from step i), as a whole, form an angle of 1-45° relative to the horizontal plane; iii) applying a polyurethane reaction system into the cavity formed in step i); and iv) solidifying the polyurethane reaction system in the cavity to form polyurethane foams, thereby forming a polyurethane concrete sandwich component, wherein the cavity between the first surface layer and the second surface layer is formed as follows: a) forming the first surface layer and the second surface layer in the first mold and the second mold respectively, wherein the first mold and the second mold each have one surface that is unclosed, wherein at least one of the first mold and the second mold have a wall height greater than the thickness of the surface layer formed in the molds; b) arranging the first surface layer located in the first mold and the second surface layer located in the second mold opposite to each other, and making each edges of the unclosed faces of the first mold and the second mold contact and having them sealed, thereby forming a cavity between the first surface layer and the second surface layer. i) forming the first surface layer and the second surface layer in molds, wherein the first surface layer and the second surface layer are arranged opposite to each other, and the opposite faces of the first surface layer and the second surface layer are arranged spaced apart from each other, i.e., forming a cavity; ii) making the two surface layers arranged opposite to each other in the molds obtained from step i), as a whole, form an angle of 1-45° relative to the horizontal plane; iii) applying a polyurethane reaction system into the cavity formed in step i); and iv) solidifying the polyurethane reaction system in the cavity to form polyurethane foams, thereby forming a polyurethane concrete sandwich component, a) forming the first surface layer and the second surface layer in the first mold and the second mold respectively, wherein the first mold and the second mold each have one surface that is unclosed, wherein at least one of the first mold and the second mold have a wall height greater than the thickness of the surface layer formed in the molds; b) arranging the first surface layer located in the first mold and the second surface layer located in the second mold opposite to each other, and making each edges of the unclosed faces of the first mold and the second mold contact and having them sealed, thereby forming a cavity between the first surface layer and the second surface layer.