A mold for improving solidification speed of an aluminum alloy cast hot section includes a top mold, a side mold and a lower mold, the top mold being arranged at top and configured to complete a back cavity of a wheel, the bottom mold being arranged below the top mold and configured to complete shaping of a front wheel disc of the wheel, the side mold being arranged on side of the top mold and bottom mold, the top mold, side mold and bottom mold jointly surrounding a cast cavity of the aluminum alloy wheel, the center of the top mold includes a step hole through which a shunt cone is mounted, the shunt cone is connected with the top mold by bolts; the upper part of the shunt cone is assembled with the center hole of the top mold of the mold, the two are in zero clearance fit.