A method of fabricating a thin film transistor substrate for a display device is provided. The method includes the steps of forming a gate line and a gate electrode connected to the gate line; forming a gate insulating film disposed covering the gate line and the gate electrode; forming a semiconductor layer a on the gate insulating film; forming a data line on the gate insulating film intersecting the gate line with the gate insulating film between the data line and the gate line to define a pixel region, a source electrode connected to the data line, a drain electrode opposed to the source electrode with the semiconductor layer therebetween, and a first upper storage electrode overlapping the gate line with the gate insulating film and the semiconductor layer therebetween; forming a protective film disposed covering the gate line, the data line, and the thin film transistor; and forming a pixel electrode connected on a side surface basis to the drain electrode and the first upper storage electrode, and a second upper storage electrode connected via a first contact hole to the first upper storage electrode on a side surface basis.