The utility model discloses a steel plate reinforced lightweight high-strength environmental protection material-saving type construction formwork which comprises a core layer, an upper layer and a lower layer, wherein an upper enhancement layer is compounded between the upper surface of the core layer and the upper layer, and a lower enhancement layer is compounded between the lower surface of the core layer and the lower layer; the core layer is a foamed plastic board, the upper enhancement layer and the lower enhancement layer are steel sheets, and the upper layer and the lower layer are plastic boards. According to the utility model, a plastic board material is used as the material of a surface layer of the construction formwork and the construction formwork has excellent impact resistance, rigidity, flame retardancy and water resistance and high surface finish. The core layer and the surface layer are enhanced by the steel sheets, so that the strength is higher. A plastic foam material is used as the material of the core layer of the construction formwork to lower the template unit area weight. The surface layer and the core layer can both adopt materials such as recyclable polypropylene to lower the production cost. The construction formwork disclosed by the utility model has good mechanical properties and small apparent density, can be recycled by a plurality of times, is convenient to operate, facilitated in improving the construction efficiency, material-saving and environment-friendly and can be widely used in the concrete pouring construction.