A technique for image storage and reconstruction based on the superposition of multiple grating-modulated images is experimentally introduced. Blazed gratings with different groove orientations and groove angles are used to superpose many gray-scale images into a single phase element. In the experiment, the phase distribution of the superposed images is loaded onto a spatial light modulator (SLM) with a computer to modulate the incident beam. The laser beam is then Fourier transformed by a convex lens. A pinhole is used to filter the desired diffraction spot of an image in the frequency domain. Another convex lens is used for image reconstruction, and a CCD camera is used to record the reconstructed images. The experimental results demonstrate that 22 gray-scale images can be stored in a phase element and reconstructed with high fidelity. The method has advantages such as high-volume data storage, easy implementation, high security, and so on.