The invention provides an organic thin film transistor array substrate, comprising: a substrate, having a liquid crystal display area and an organic thin film transistor area; a pixel electrode, formed on the substrate in the LCD area; a first alignment film, formed on the pixel electrode; a second alignment film, formed on the substrate in the OTFT area; an organic semiconductor layer, formed on the second alignment film, wherein the organic semiconductor layer is aligned along the direction of the second alignment film; and a gate, a source and a drain, formed in the OTFT area, wherein the source and the drain are in contact with the organic semiconductor layer and a channel is formed between the source and the drain.