The present invention relates to a polyarylate film having high level of negative phase difference toward out of plane direction, which is good enough to be used as an optical compensator film providing wide view angle. The polyarylate film prepared in the present invention has bigger birefringence toward out of plane direction than that of polymer for the conventional compensator film, suggesting that it not only reduces the thickness of the final product but also has the effect of optical compensation only with thin film coating.