A liquid crystal display device having a simplified manufacturing process is disclosed. The liquid crystal display device includes a gate line and a common line having a first conductive layer group having at least double conductive layers. A common electrode is formed by an extension of at least one transparent conductive layer of a common line. A portion of the common electrode is formed of one conductive layer of the first conductive layer group, while a remaining portion of the common electrode is formed of the first conductive layer group. The gate line, a source electrode and a drain electrode have a second conductive layer group having at least double conductive layers, and the pixel electrode is formed by an extension of at least one transparent conductive layer of the drain electrode.