The invention discloses a rear door plate component and a vehicle inspection-free label self-issuing machine thereof. The rear door plate component comprises a rear door plate, wherein one side of therear door plate is hinged with a side plate through a rear door hinge, the other side thereof is provided with a rear door lock, one end, close to the rear door plate, of a lower back plate is provided with a rear lower lock plate, one end, close to the rear door plate, of an upper back plate is provided with a rear upper lock plate, the rear lower lock plate and the rear upper lock plate are separately assembled with one end of a rear lock rod, so as to lock the rear door plate, the other end of the rear lock rod is hinged with one end of a rear lock connection rod, the other end of the rearlock connection rod is assembled and connected with one end of a rear lock drive rod, the other end of the rear lock drive rod is assembled in the rear door lock, one end, driving the rear lock driverod and the rear lock connection rod to assemble, is provided with a rear lock assembling groove, the rear lock assembling groove and the rear lock connection block are assembled and fixed, and the rear lock connection block is arranged on the rear lock connection rod. Through adoption of the rear door plate component and the vehicle inspection-free label self-issuing machine thereof, six-year inspection-free labels can be printed and issued automatically, so that labor intensity of workers at the window is lowered, and the working efficiency is improved.