The present invention relates to a substrate for a liquid crystal display device and a liquid crystal display device which are used as, for example, a display unit of an electronic apparatus, and an object of the present invention is therefore to provide a substrate for a liquid crystal display device and a liquid crystal display device capable of providing high transmittance, high luminance, and good display characteristics as well as a high production yield. A substrate for a liquid crystal display device is provided with a storage capacitor bus line formed approximately parallel with a gate bus line, a first pixel electrode connected electrically to the source electrode of a transistor, a second pixel electrode formed so as to be opposed to part of the source electrode of the transistor via an insulating film and to be separate from the first pixel electrode, and a slit formed between the adjoining end portions of the first pixel electrode and the second pixel electrode and having a slit width which is greater than a shortest width in a region over the storage capacitor bus line.