A photosensitive resist is prepared through using 5-30 parts of a colloid, 0.1-0.7 parts of a photosensitive agent, 30-80 parts of water and 0.01-0.05 parts of an antifoaming agent; the colloid comprises one or more of polyvinyl alcohols having a polymerization degree of 300-2000 and an alcoholysis degree of 80-99mol%; the photosensitive agent is ammonium dichromate or comprises one or more of diazo compounds comprising diphenylamino-4-diazo salt, trimethoxy-4-diazodiphenylamino salt, a diphenylamino-4-diazo salt grafted compound, a trimethoxy-4-diazodiphenylamine compound, 2-diazo-1-naphthoquinone-4-sulfonyl chloride and the like and is processed to prepare an aqueous solution having a mass percentage concentration of 3-7%; and the antifoaming agent is a water-based organosilicon modified emulsion-like antifoaming agent. The obtained photosensitive resist has a lower viscosity than general photosensitive resists, steel band can be uniformly coated by the photosensitive resist, there are no spots after the coating of photosensitive resist on the steel band visually, and the technical problems of easy cracking, easy foaming and the like caused by the too high viscosity of present photosensitive resists in the subsequent application are effectively avoided.