The invention discloses an aqueous solution of silk fibroin and a preparation method for the aqueous solution, and belongs to the technical field of biomedicine. According to the technical scheme, the method comprises the following steps of: adding strongly polar polyol or soluble salt for hindering gelatinization of a silk fibroin solution into the silk fibroin solution, performing high-temperature steam sterilization, and thus obtaining the aqueous solution of the silk fibroin, wherein the aqueous solution of the silk fibroin can be stored for over 3 months at room temperature without gelatinization or deterioration and has stability. The aqueous solution of the silk fibroin is suitable to be prepared into various silk fibroin films, hydrogel, porous materials, microspheres and the like used for cosmetics, skin-care products, sun lotion, tissue engineering materials, medicament carriers, artificial skin and the like. Because the stable aqueous solution of the silk fibroin can be stored for long time, the preparation-and-use workshop type production mode of a silk fibroin biomaterial can be changed into a large-scale industrialized production mode.