The invention discloses a fixture used for a numerical control machine tool. The fixture comprises a base, a mold core and a cover plate. The base is provided with a positioning groove. The mold core is embedded in the positioning groove. The upper edge of the mold core is a certain distance away from the inner wall of the positioning groove. A product is arranged on the mold core. The cover plate is pressed and held on the product. Liquid inlet holes are formed in the bottom of the base. Liquid spray holes penetrating the liquid inlet holes and the positioning groove are formed in the top of the base, and the multiple liquid spray holes are formed along the periphery of the positioning groove. By means of the fixture used for the numerical control machine tool, the aim of cooling the product in a 360-degree dead-corner-free manner, tools can be well cooled, the highlight face machining quality of the product is improved, and the service life of the tools is prolonged. The invention further discloses the numerical control machine tool comprising the fixture used for the numerical control machine tool.