In this study, the ion beam irradiation method on organic (polyamic acid and epoxy resin compound) overcoat layer was investigated. The use of ion beam on overcoat organic layer has the potential to replace conventional rubbing process. The traditional alignment layer is made by coating process and 2 times heat treatment on polyamic acid liquid. It requires many times and process steps. However, it is very economic and convenient process substitute polyimide alignment layer for organic overcoat. In order to characterize the LC alignment the polarized microscope image and pretilt angle measurement were investigated. The good LC aligning capabilities treated on the organic overcoat thin film surfaces with ion beam exposure of 45° at above ion beam energy density of 1200 eV were achieved.