To provide an economic recovery molding flask and its manufacturing method capable of reducing the material cost and reducing the demolition cost.

A used molding flask is demolished and a plate material 20 is separated from a plate frame 10. Severely damaged both end parts 21, 21 of the plate material 20 are cut off. Reusable central part 22 is nailed to the frame 10 and reused. To compensate short parts, plate materials 23 taken from the used molding frame are added connectedly for use. A polyester resin paint or urethane resin paint is applied on the surface of the plate materials 22, 23, and a glass fiber sheet 31 is laid thereon, and further, the polyester resin paint or an urethane resin paint is applied. After drying, moreover, the urethane resin paint is applied thereon. By forming a resin coating layer 30 in which glass fibers 31 are painted in the resin layer 32, scores and joints are filled to smooth the surface. The plate materials 22 are left without removing from the wooden frame 10 as they are, and removal of nails can be omitted.