Gear steel for high temperature rapid carburization automobile

The invention relates to gear steel for a high temperature rapid carburization automobile. The gear steel for the high temperature rapid carburization automobile comprises the following chemical ingredients in percentage by mass: 0.19-0.25% of C, 0.20-0.41% of Si, 0.5-1.33% of Mn, 0.4-1.45% of Cr, 0.01-0.6% of Ti, 0.02-0.35% of Al, 0.085-0.23% of Nb, 0.001-0.35% of Ni, 0.04-0.35% of Mo and the balance of Fe and inevitable impurities. The gear steel for the high temperature rapid carburization automobile has the advantages that Nb, Al, Ni and Ti are added, crystal grains are refined, hardenability range of steel is stabilized, toughness of steel is improved and fluctuation range of product hardness of is reduced while hardenability of steel is enhanced and comprehensive mechanical properties of the steel are improved, so that deformation is small after the gear steel is subjected to heat treatment, and matching ratio is increased; meanwhile, a blending structure is reasonable, so that cost of raw materials is reduced, and benefit of steel is increased.