The technical field of liquid crystal display is related to. A pixel unit is provided. The pixel unit includes a storage capacitor that is arranged on an array substrate. The storage capacitor includes a first electrode arranged on a first metal layer and a second electrode arranged on a second metal layer. An insulation layer is arranged between the first electrode and the second electrode. The second electrode and the first electrode overlap with each other to form a first overlapping region, an area of which does not change if a deviation of the second electrode relative to the first electrode is within a preset distance. Storage capacitor difference among different pixel units generated by alignment accuracy difference thereof can be eliminated, and watermark which would be generated otherwise can be eliminated as well. An array substrate is further provided, which includes the storage capacitor of the aforesaid pixel unit. A quality of a product can be improved.