The most suitable blade inclination angle for multiphase flow in soybean milk machine is obtained by simulating the gas-liquid two-phase flow field. The result shows that the lower blade A has a greater influence on the internal flow of soybean milk machine than the upper blade B. As the angle magnitude of alphaA increases, the peak value of radial velocity decreases and moves to the interior of the cavity, so does the total pressure. When alphaA changes from -24° to -26°, the velocity vector at the bottom of the cavity changes from the connected state to the separated state, and the pressure difference between the up and the bottom surface of blade A becomes large. When alphaA=-24°, both the turbulent kinetic energy and dissipation are large. When alphaB=28°, the pressure difference reaches the maximum. In summary, the best inclination angles are alphaA=-24°~-26° and alphaB=28°, respectively.