An electronic device including a waterproof structure is provided. The electronic device includes a housing including a first plate oriented in a first direction, a second plate oriented in a second direction opposite to the first direction, and a side surface member surrounding a space between the first plate and the second plate, and a display panel disposed between the first plate and the second plate. The display panel includes a flat area including an active area configured to emit light toward the first plate, and a connection area extending from at least a partial area of one edge of the flat area and is disposed between the first plate and the second plate, a polarizing plate disposed on the flat area, and a filler member spaced apart from the connection area and disposed on the one edge of the flat area, wherein the one edge of the flat area includes a cut surface bent in a stepped shape in an area on which the filler member is disposed, and a part of the cut surface includes a shape in which a boundary of the display panel coincides with a boundary of the polarizing plate.