Abstract: To clarify the effects of extrusion parameters on the quality and beany flavor of high-moisture extruded textured soy protein (extruded protein), soy protein isolate, soy protein concentrate, and low-temperature defatted soybean meal (SBM) were used as raw materials. The effects of SBM addition, extrusion temperature, cooling temperature, screw speed, feeding speed, and moisture content on anisotropy, texture properties, degree of texturization (DT) and key beany flavor compounds for extruded protein were systematically investigated. In addition, correlation analyses were conducted between these parameters and the DT and the concentration of key beany-flavor compounds in the extruded protein. The results indicated that the extrusion input parameters significantly influenced its quality characteristics and beany flavor of extruded protein. Optimal extrusion conditions were 40% SBM, extrusion temperature of 150 ℃, cooling temperature of 60 ℃, screw speed of 360 r/min, feeding speed of 10 kg/h, and moisture content of 60%, respectively. The extrude protein produced under each optimal parameter exhibited enhanced surface smoothness, a brighter color, and improved textural properties and DT, while maintaining relatively low concentrations of key beany flavor compounds. Correlation analysis indicated that cooling temperature had the strongest impact on DT(P<0.05), and a negative correlation was observed between DT and key beany flavor compounds. Molecular docking confirmed potential non-covalent interactions between extrude protein and key beany flavor compounds. These findings indicated that targeted modulation of extrusion parameters can enhance fiber formation while controlling beany flavor, providing guidance for the industrial production of low-cost, high-quality PBMA.