The present invention relates to a medical cast was made a double structure. The present invention is the medical cast, contact the patient's affected area, the functional fiber for improving the adhesion between the skin mix at least two kinds woven, diamond network hole network forms are formed skin protective equipment is manufactured as; is configured to wrap the outside of the skin protection, improvement and the inner surface supporting cast to absorb the sweat and waste during the cast, wrap the outer surface of the inner surface of the supporting cast, the breathability to wrap the outside of and the inner supporting cast; that and the inside ventilation channels to be, and the adhesion reinforcing portion to improve the cast of stretchable, inner supporting cast is the inner rigidity reinforcing portion is configured to provide a primary rigidity of medical cast is configured, the hydraulic hardening liquid is impregnated, an outer ventilating channel formed along an outer peripheral surface, the outer airflow channel coupled configuration, the adhesion reinforcing portion which provides a predetermined stretching force is formed, on the outer side a surface has a feature that it comprises a cutter unit for guiding the traveling direction of the cutter blade, it is configured on both sides of the cutter portion, an outer support casting to the outer rigid reinforcement portion is formed to provide a secondary rigidity of the medical plaster to provide a medical cast to.