Grinding mechanism and tobacco cutter

The utility model discloses a grinding mechanism and a tobacco cutter, the grinding mechanism comprises a support, a rotatable knife roll, a movable knife grinding device and a reciprocating motion device are arranged on the support, a plurality of blades used for cutting tobacco leaves are arranged in the circumferential direction of the knife roll, a grinding wheel used for grinding the blades is arranged on the knife grinding device, and the reciprocating motion device is arranged on the support. The reciprocating motion device is used for driving the knife grinding device to do linear reciprocating motion and pause working when the knife grinding device reaches a designated position, a feeding assembly is arranged on the knife grinding device, and the feeding assembly is used for driving the grinding wheel to feed or retreat in the radial direction of the knife roll when the knife grinding device reaches the designated position. And the grinding wheel grinds a groove structure on the cutting edge part of