The present application discloses a low-pressure casting secondary pressure process for an aluminum wheel. The characteristics of smooth low-pressure filling of molten aluminum alloy and rapid solidification of a rim are preserved, the aluminum alloy at a center sprue is frozen by using a center sprue spreader and a forced water coolling to close a mold cavity, and secondary pressure is implemented to the aluminum wheel by means of down-movement of center extrusion rods, so that the material mechanical properties of an aluminum wheel casting and the production efficiency of the casting process are improved.