The invention discloses a simple rough body eliminating instrument. The simple rough body eliminating instrument comprises a dust isolation plate, a fixed pipe, a supporting disc, a connecting pipe, blowers, blowing openings and a power center, wherein a rotating part is mounted below the supporting disc, a length controller is mounted in the supporting disc, and the length controller is connectedwith the fixed pipe through an elastic device; the dust isolation plate is mounted on the left side of the fixed pipe, the power center is mounted below the blowing openings, a rotating device is mounted in the power center, and an air exhaust fan is mounted above the rotating device; an error alarm is mounted on the surface of the power center, the power center is connected with a grinding partthrough a transmission rod, and a grinding device is mounted on the left side of the grinding part; and an air exhaust pipeline is mounted below the fixed pipe, the corresponding blower is mounted onthe right side of the air exhaust pipeline, and a material bin is mounted below the blower. According to the simple rough body eliminating instrument, through the action of the grinding device in an isolation plate and the blowers, the grinding performance is improved while the dust emission is reduced, and an environment-friendly function is further provided during using.