The invention belongs to the field of automobile manufacturing, relating to a jackshaft part in an automobile power transmission system and the manufacturing technology thereof. The process adopts hyposteel bars of normalized condition as the raw stock, and heats the bar raw stock to 900 DEG C for extrusion molding. The entire extrusion molding process comprises the following extrusion technology: forward extrusion molding technology, overall backward extrusion molding technology, long-hole extrusion molding technology, drawing-down extrusion molding technology and diameter extension extrusion technology; wherein, the number of the working steps of the extrusion technique required in the extrusion molding procedures of the jackshaft parts with different structures and dimensions is different; the temperature of the metal material reduces from 900 DEG C to 100 DEG C; the extrusion workpiece, the shape and dimension of which is similar to that of jackshaft part finished product, is obtained, and the part is manufactured after mechanical cutting processing procedure, alignment and inspection procedures. After the entire extrusion molding is finished, the bending strength, shear strength and impact ductility of the extrusion workpiece are superior to the mechanical performance index of a test bar of the same material which is subject to hardening and tempering as well as heat treatment, and the tensile strength is similar to the test bar of the same material which is subject to hardening and tempering as well as heat treatment; the elastic torsion angle of the hollow jackshaft is larger than 120 degrees.