A substrate for display device is provided. As a wiring structure of the substrate, the scan line layer and the signal line layer are not connected directly by arranging through-holes between the scan line layer and the signal line layer, but are connected through an ITO layer by arranging through-holes between the scan line layer and the ITO layer and arranging through-holes between the signal line layer and the ITO layer, with an object to reduce the value of the connection resistance between the scan line layer and the signal line layer. Through-holes connecting the scan line layer and the ITO layer and through-holes connecting the signal line layer and the ITO layer are configured in a comb shape respectively and engaged with each other. Thus the length of the ITO connecting the scan line layer and the signal line layer becomes shorter and the value of the connection resistance is reduced.