Disclosed in the present application is a low-pressure casting mold for an aluminum wheel. V-shaped grooves are formed in the cavity surface of a side mold, a cavity is formed in the back cavity of the side mold, a cooling duct is arranged in the cavity of the side mold, and a main air pipe is perpendicular to an annular branch; the annular branch is concentric with a wheel casting, and air pipes are 5-10 mm away from the bottom surface of the cavity; the two ends of the annular branch are welded with plugs; air outlet holes are arranged on the annular branch, and the holes are perpendicular to the bottom surface of the cavity; the diameters of the air outlet holes are 3 mm, and the holes are uniformly distributed at intervals of 10-15 mm in the circumferential direction.