In an electro-optical device substrate, first and second pixel switching elements each include a gate electrode formed of a first conductive film, a gate insulation film formed of a first insulation film, a semiconductor layer, a source electrode formed of a second conductive film, and a drain electrode formed of the second conductive film. A first storage capacitor includes a first storage capacitor electrode formed of the second conductive film, a protective film formed of a second insulation film so as to over at least the first storage capacitor electrode, and a pixel electrode formed so as to overlap with the first storage capacitor electrode at least partially with the protective film interposed therebetween.