The invention discloses a process for machining a corrugated pipe fitting by means of an electromagnetic pre-deformation forming technique. The process includes the steps of (1) pipe fitting installation and (2) discharging forming of the corrugated pipe fitting, wherein in the step of pipe fitting installation, the pipe fitting is fixed well through a pipe fitting restraint device, the pipe fitting restraint device is overlapped with the axis of the pipe fitting, and a solenoid coil is arranged in the portion, needing to form, in the pipe fitting; in the step of discharging forming of the corrugated pipe fitting, the electric capacity of a charging capacitor set of the solenoid coil is 768-1152 mu F, a discharging control switch is turned off, the capacitor set is discharged through the solenoid coil, expansion and deformation of the pipe fitting are caused and corrugation is formed. The process has the following technical advantages that the corrugated aluminum alloy energy-absorption pipe fitting is machined by means of the electromagnetic pre-deformation forming technique, the method is easy and convenient to carry out, operations are easy to carry out, the forming speed is high, and cost is saved; the shape and the size of corrugation can be effectively controlled, and adaptability needed by energy absorption is flexible; yield strength of materials on the expansion portion is quite different from that on the trough positions, the strength of the pipe fitting in the axial direction is different, and the deformation mold is controllable; and energy absorbing efficiency of a thin-walled round pipe can be obviously improved.