The invention relates to the technical field of injection molds, and discloses an injection mold. The injection mold comprises a hydraulic device, a hydraulic rod movable mold and a fixed mold, wherein the hydraulic device is in transmission connection with the movable mold through a hydraulic rod, a mold cavity is formed between the movable mold and the fixed mold, a cooling water channel is formed in the mold cavity, a pouring opening is formed in the middle of the fixed mold, the pouring opening communicates with the mold cavity and communicates with an injection molding machine, the middleof the movable mold is in a groove shape, the groove communicates with the mold cavity, a sealing piece is driven to move downwards under the action of a hollow electromagnet, and therefore gradually-changed negative pressure is formed between the sealing piece and the movable mold firstly. The gradually-changed negative pressure acts on the injection molding piece, slow separation between the outer wall of the injection molding piece and the inner wall of the fixed mold can be guaranteed, bonding resistance between the injection molding piece and the fixed mold disappears, separation from the fixed mold is achieved while the movable mold moves downwards, in the demolding process, the surface of the injection molding piece is not bonded with the fixed mold during demolding, resistance isrelatively small, and the surface quality of the injection molding piece during demolding is improved.