The invention discloses a medicine grinding device. The medicine grinding device comprises a base, a bracket device, a frame body device, a grinding device, a blowing device and a material receiving box, wherein the bracket device comprises a first bracket and a second bracket; the frame body device comprises an upper frame body, a lower frame body, a first fastening device, a second fastening device and a first rectangular hole; the upper surface of the material receiving box is concave downwards to form a material receiving cavity; the lower surface of the upper frame body is concave upwards to form a first containing cavity; the upper surface of the lower frame body is concave downwards to form a second containing cavity; the first fastening device comprises a first horizontal rod, a first fastening rod and a second horizontal rod; the second fastening device comprises a connecting rod and a third horizontal rod; the grinding device comprises a positioning plate, a first supporting rod, a supporting column, a spring, an ejecting rod, a grinding wheel, a fixed block, a pushing rod, a cylinder, a second supporting rod and a third supporting rod; and the blowing device comprises a blowing pipe, a fan, a fourth supporting rod and a fifth supporting rod. The medicine grinding device disclosed by the invention has the advantages that the structure is simple, the use is convenient, the medicines can be effectively ground and the grinding effect is good.