An array substrate and a liquid crystal display device comprising the array substrate are disclosed. The array substrate comprises a pixel unit having a thin film transistor region and a through-hole region. The pixel unit comprises a glass substrate, a first insulation layer, a second insulation layer, a third insulation layer, a fourth insulation layer, and a fifth insulation layer stacked from bottom up in sequence. In the thin film transistor region, the glass substrate is provided with a light-shading metal member that is covered by the first insulation layer, the first insulation layer is provided with an active layer that is covered by the second insulation layer, two ends of the active layer are respectively connected with a source and a drain formed between the third insulation layer and the fourth insulation layer, the second insulation layer is provided with a gate that is covered by the third insulation layer, and the fourth insulation layer is provided with a common electrode that is covered by the fifth insulation layer. In the through-hole region, a pixel electrode is arranged on the fifth insulation layer and a through hole is configured in the fourth insulation layer, so that the pixel electrode is connected with the source or the drain after passing through the fifth insulation layer. A cushion layer is arranged under the through hole in an insulated manner.