A display device includes: a light emitting element on a substrate; a third-first transistor and a third-second transistor connected in series between a gate electrode of the first transistor and a drain electrode of the first transistor; a first metal layer on the substrate and comprising a gate electrode of the third-first transistor and a gate electrode of the third-second transistor; a hydrogen passivation layer on the first metal layer; a semiconductor region of each of a first transistor, the third-first transistor, and the third-second transistor on the hydrogen passivation layer; a gate electrode on the capping layer; a first bias electrode on a same layer as the gate electrode of the first transistor and overlapping the semiconductor region of the third-first transistor; and a second bias electrode on a same layer as the first bias electrode and overlapping the semiconductor region of the third-second transistor.