The invention relates to a milling cutter. The milling cutter comprises a cutter handle and a cutter head, wherein the cutter head is provided with cutter teeth. The milling cutter is characterized in that a storage groove is formed in the center of the cutter head, a fluid passage is formed in each cutter tooth and is communicated with the storage groove, a one-way stop membrane is arranged on one end, away from the storage groove, of each fluid passage, an axial fluid input passage is formed in the center of the cutter handle and is communicated with the storage groove, and a one-way stop membrane is arranged in the fluid input passage. By adopting the scheme, the milling cutter is simple in structure and convenient to use; a machining groove or a machining surface is washed by virtue of fluid flowing out from the fluid passages, so that residues can be effectively removed.