The utility model discloses an automatic paper shredder. The automatic paper shredder comprises a machine cover, a paper supporting box, a shell, a paper supporting plate, a paper supporting plate paper inlet, a paper shredding component, a driving motor, a paper pressing plate, a paper rubbing component and a wastebin, according to the automatic paper shredder, due to the design of the spliced paper pressing plate, the paper pressing effect is effectively improved, meanwhile, due to the fact that the damping plate, the soft rubber sheet and the convex ribs are additionally arranged, the paperrubbing effect is effectively improved, and the paper shredding efficiency is further improved. The automatic paper shredder has the advantages of being high in automation degree, convenient to use,safe, reliable, ingenious in design, simple in structure, economical in cost and the like.