A TFT array substrate including a substrate, a plurality of pixel structures and a plurality of cutting marks is provided. The substrate has a device region and a cutting mark region. The pixel structures are disposed in the device region and each pixel structure includes a TFT, a pixel electrode and a passivation layer covering the TFT. The cutting marks are within the cutting mark region, disposed at two sides of a predetermined cutting position, and are arranged as a row or column perpendicular to a predetermined cutting direction. In particular, the cutting marks are constituted of at least two colors, at least two shapes, at least one color and at least one shape, or a combination thereof.