The invention discloses a natural graphite crushing device for lithium battery processing. The natural graphite crushing device comprises a supporting mechanism, an extrusion mechanism, a first crushing mechanism and a discharging port, wherein the supporting mechanism comprises a crushing box, supporting legs, a sealing door, a top cover and a feeding port, the front side of the crushing box is rotationally connected with the sealing door, the top cover is arranged at the top of the crushing box, the outer sides of extrusion plates are connected with hydraulic cylinders, the hydraulic cylinders are arranged at the tops of the supporting legs, the first crushing mechanism is arranged below the extrusion mechanism, and a second crushing mechanism is arranged below the first crushing mechanism. According to the natural graphite crushing device for lithium battery processing, the hydraulic cylinders are arranged, the hydraulic cylinders can drive crushing cutters on the extrusion plates to extrude and crush graphite in a circulating and reciprocating mode, meanwhile, a screening net is arranged, the screening net can filter graphite particles crushed for the first time, and the graphite blocks with overlarge sizes remain on the screening net and are extruded by the crushing cutters again, so that the crushing uniformity can be ensured to a certain extent.