A display device and a manufacturing method of a display device are provided. A display device includes: a substrate; a semiconductor layer on the substrate; a source electrode and a drain electrode on the semiconductor layer; an auxiliary electrode on a same layer as the source electrode and the drain electrode; a first electrode electrically connected with the source electrode or the drain electrode; a light emitting element layer on the first electrode; and a second electrode on the light emitting element layer, and the auxiliary electrode includes at least one groove located inside the auxiliary electrode.