This invention relates to a photocatalyst used for processing organic wastewater or pollution air, in addition to a preparing method. The catalyst uses the glass spring as the carrier, coating titania photocatalyst film in the glass spring surface, wherein the film is doped with titania particles. The surface after coating has a concave-convex shape because of particles, which can increase the specific surface area of the photocatalyst; the ultraviolet light passes through the gap of the glass spring, which can increase the flux and conveying distance, and shin more titania film surface, so to increase the efficiency of the photocatalyst.