Provided is a first-aid plaster which is plastered on a skin surface of the affected part such as a wound, an insect bite or the like to perform medical treatment, disinfection or the like of the affected part, which is characterized by preventing a delay of recovery of the affected part or pigmentation of the skin by the penetration of ultraviolet rays. The first-aid plaster is so constituted that a pad member 3 is plastered on a central part of an adhesive sheet 1 with the pad member 3 covered by separate paper 4 and 5 removably plastered on the sheet 1, wherein the above pad member 3 is composed of a pad 31 which is formed by a gauze, a nonwoven fabric, a web or the like and an ultraviolet ray blocking film 32 which is disposed in or under the pad 31, and the pad member is constituted to be wrapped by a net 34.