A substrate for a display device includes an insulating substrate, a data line, an insulating layer and a pixel electrode. The insulating substrate has a switching element. The data line is formed on the insulating substrate to be electrically connected to a first electrode of the switching element. The insulating layer is formed on the insulating substrate having the switching element and the data line. The insulating layer has a contact hole through which a second electrode of the switching element is partially exposed and a groove adjacent to the data line. The pixel electrode is formed on the insulating layer to be electrically connected to the second electrode through the contact hole. Therefore, an image display quality may be improved, and a manufacturing cost of the LCD device may be reduced.