The invention discloses a carburization quenching tool for a crankshaft. The carburization quenching tool comprises a flat plate and vertical columns, wherein the flat plate is provided with an upper surface, a lower surface and a plurality of carburization quenching units, wherein through holes are positioned in the centers of the carburization quenching units; the circle centers of 3 crankshaft positioning small holes and the circle centers of 3 crankshaft positioning large holes are uniformly distributed on the same circumference, with R serving as a radius, of the carburization quenching units; the diameters of the crankshaft positioning small holes are D1, and the diameters of the crankshaft positioning large holes are D2; the diameters of the through holes are D3 (D1=(0.65-0.99)xD3 and D2=(1.01-1.35)xD3); R is greater than 0.5x(D2+D3); the diameter D3 of each through hole is 8 to 72 mm, and the diameters of the crankshaft positioning small holes and the crankshaft positioning large holes of different carburization quenching units can be the same or different. The carburization quenching tool for the crankshaft is simple in structure, and the carburization quenching deformations of the crankshaft and a crankshaft spline can be reduced; therefore, the number of charging types is increased, and the charging volume of the crankshaft is enlarged.