PURPOSE: To simply strengthen the rigidity of a low-cost outer peripheral flange having weak rigidity in an interior trim part for a vehicle using a rigid urethane core material filled with middle glass fiber and a method for manufacturing the same.

CONSTITUTION: After a skin material 30 set on the surface of a cavity mold 40 is coated along the inner surface of the outer peripheral edge of the material 30 with adhesive 71, reinforcing fiber 80 such as middle glass fiber is coated on the coated surface of the adhesive 71, then a core mold 50 is clamped to the mold 40, rigid urethane resin solution mixed with the glass fiber is injected to be filled in the cavity at a high pressure via the injection head 61 of a high- pressure injection unit 60, and foamed to be reacted. Thus, the mixing ratio of the reinforcing fiber such as the glass fiber is enhanced as compared with the general part of the rigid urethane core material, thereby partly reinforcing it simply.