A display device including a lower substrate having a display region including a plurality of pixel regions, and a peripheral region surrounding the display region; a plurality of pixel structures in the plurality of pixel regions on the lower substrate; an upper substrate on the plurality of pixel structures; a seal between the lower substrate and the upper substrate in the peripheral region; and a power supply voltage wiring between the seal and the lower substrate in the peripheral region, wherein the power supply voltage wiring partially overlaps the seal, and the power supply voltage wiring includes a plurality of first openings in a portion thereof that protrudes inwardly from the seal in a first direction extending from the peripheral region into the display region.