The invention discloses a preparation method for a silver iodide-loaded photo-catalytic material. The photo-catalytic material has high specific surface area and excellent visible-light response property. The preparation method comprises the following steps: a) dropwise adding silver nitrate and iodine compound into a nonionic surfactant solution, stirring under light-shielding state and ultrasonically treating, thereby acquiring a nanometer silver iodide complex; b) adding nonionic surfactant, cosolvent, solvent and water into a reactor, heating to 45-60 DEG C, stirring till fully dissolving, and then adding the nanometer silver iodide complex and uniformly stirring; and c) adding a molecular sieve, dipping for 6-24h and then filtering, washing and roasting an acquired sample for 4-8h at 350-450 DEG C, thereby acquiring the silver iodide-loaded photo-catalytic material.