The optical storage characteristic of the D96N genetic mutant bacteriorhodopsin film is experimentally studied, where the optical image is recorded on the BR film with 670 nm laser, the readout of the image is carried out by a weak 560 nm light, and the erase of the image is completed with the illumination of 488 nm laser. The lifetime of the M state is measured to be extended to 3 minute at room temperature, which is five-order magnification longer than that of the wild type bacteriorhodopsin in the solution.