The invention relates to a simple and high yield process for producing a regenerated silk fibroin which does not need dialysis. Particularly, a process of the invention is characterized in that the silk fibroin is precipitated by applying a shear stress and/or changing the solvent power of the fibroin solution. The process of the invention simplifies the process of producing silk fibroin and greatly shortens the process time to 1 to 2 hours, whereas the conventional dialysis process is complex and needs around 2 to 3 days. In addition to reducing the time needed, the process of the invention can increase productivity of silk fibroin by at least 8%.