Abstract: Using subcritical sesame protein powder as the main raw material, the twin-screw extrusion technology was used to study the effect of extrusion texturing on the physicochemical properties and structure of protein raw materials, and to explore the formation mechanism of texturized protein. After extrusion, the water retention of protein materials increased by 14.16%, oil absorption decreased by 14.52%, protein digestibility increased by 11.18%, free sulfhydryl content decreased by 11.55%, and amino acid components had a certain loss. No new peptide bonds were formed during the extrusion texturing process, but a large number of disulfide bonds were formed. The structure of the texturized protein obtained by extrusion was mainly maintained by the combined action of disulfide bonds and non-covalent bonds. And the extrusion organization was not completely destroyed. The secondary structure of protein included only partially unstable α-helices and irregular coils to relatively stable β-sheets and β-turns. It could be seen that the protein material changed from disorder to order after extrusion and organization. And produced a large number of fiber structures. It would provide a theoretical basis for further study on the formation mechanism of histochemical proteins and development of histochemical sesame protein products.