The invention discloses a grinder which comprises a base, a grinding cup and a cup lid, wherein the grinding cup is mounted at the top of the base; the cup lid covers an upper opening of the grinding cup; a grinding motor is arranged in the base; a feed hopper is arranged in the grinding cup; a grinding component is arranged at the bottom of the feed hopper; the grinding component comprises a static grinding head and a dynamic grinding head in mutual cooperation; the static grinding head is fixed on the feed hopper; the dynamic grinding head is arranged in a hollow cavity of the static grinding head and fixedly connected with an output shaft of the grinding motor; in the feed hopper, a fixed baffle is arranged above the grinding component; one part of the side of the fixed baffle is connected with the side wall of the feed hopper, and the other part of the side of the fixed baffle and the side wall of the feed hopper form a discharge port; a rotatable movable baffle is arranged at the discharge port; the movable baffle fits the fixed baffle; the movable baffle rotates to intermittently open or close the discharge port; and a cavity for preventing blockage is formed between the down side of the movable baffle and the dynamic grinding head. The grinder disclosed by the invention avoids material blockage and guarantees the grinding efficiency and effect.