Abstract: A method for storing and displaying ultra-high resolution grayscale images based on metasurfaces was proposed. Combining the polarization splitting characteristics of the metal nanobricks arrays with Malus's law, the grayscale information of the image was encoded into the arrangement of nanobricks' orientation angles, thereby realizing accurate and continuous grayscale modulation. Experimental results show that a high fidelity grayscale image can be observed at the near-field of the metasurface with a high resolution of 90 714 ppi. This design method of image processing technology based on metasurfaces, which has the advantages of small volume, light weight, compact structure, and easy integration, is simple and flexible. Therefore, the proposed method indicates the potential in high-density optical information storage, high-end product anti-counterfeiting, information encryption and many other fields.