An uneven affected area is uniformly irradiated with light. A photoirradiation device includes a flexible substrate, a plurality of LED chips arranged in a matrix over the flexible substrate, walls having flexibility and surrounding the plurality of LED chips, and a protective resin, formed within the walls so as to cover the plurality of LED chips, that has translucency to transmit emitted light emitted by the plurality of LED chips and has flexibility. The emitted light is radiated from a region surrounded by the walls.
