A high precision correction method of illumination field uniformity for photolithography illumination system is proposed. The correction ability and accuracy are improved by the optimization of the fingers' fore-end shape and arrangement of the finger array uniformity corrector. The simulation results show that the correction accuracy of the finger array uniformity corrector is better than 0.2%, when fingers are staggered arrangement. In addition, the correction accuracy of the finger array uniformity corrector is better than 0.16%, when fingers are chamfered, staggered and double layouts arrangement, which is about twice as high as general finger array uniformity corrector.