The utility model discloses a special-shaped small precision part grinding device. The device comprises a rack, a grinding trolley and a rotating tool, wherein a translation unit and a workbench are fixedly mounted at the top of the rack; wherein the horizontal moving unit is located on one side of the workbench, the grinding trolley is installed on the horizontal moving unit to do linear reciprocating motion, the grinding trolley comprises an installation table, a position adjusting unit and a grinding unit, the rotating tool is fixed to the workbench, and a workpiece fixed to the rotating tool does rotating motion along with the rotating tool. Grinding is achieved through mutual surface friction between a workpiece rotating at a high speed and the grinding unit on the grinding trolley doing linear reciprocating motion, the original position precision is not changed, the efficiency and the product percent of pass are improved, the product quality is stable, the labor intensity is reduced, and batch production is achieved.