The invention belongs to the technical field of powder metallurgy, and relates to a powder metallurgy preparation method of a double-clutch large-torque automatic gearbox synchronizer gear hub. The powder metallurgy preparation method comprises the following steps of material mixing, forming, pre-sintering, shaping, machining, deburring, sintering hardening, tempering, partial shot blasting, cleaning and packaging. According to the synchronizer gear hub produced by the preparation method, the tensile strength is increased, and the fracture risk caused by increase of the torque of a transmission is reduced; the production efficiency of shaping, machining and deburring is improved, the risk of shaping cracks is effectively avoided, loss of material of a machining tool, a deburring brush andthe like is greatly reduced, production energy consumption is greatly reduced, the high-frequency quenching process is omitted, the product quality is improved, the comprehensive cost is reduced by 20% or above on the basis of the original foundation, and the preparation method is suitable for large-scale production of the double-clutch large-torque automatic gearbox synchronizer gear hub throughpowder metallurgy.