The invention discloses a die-casting die with shearing and extruding functions. A main structure of the die-casting die comprises a male die body, a female die body, a left baffle, a right baffle, bolt nuts, a V-shaped cavity, a vacant cavity, an upper vacant groove, a lower vacant groove, an upper pressing block, a lower pressing block and an overflow groove. The die-casting die with the shearing and extruding functions is designed for solving the problems that in the traditional magnesium alloy die casting process, shrinkage cavities, shrinkage porosity, cracks, inner air holes and other defects are likely to happen. The male die body is a rectangular body with an oblique face. The female die body is in a V-shaped groove shape. An oblique face part of the male die body is connected with an oblique face part of the female die body in a matched manner, and the oblique face part of the male die body and the oblique face part of the female die body are the same in angle. When magnesium alloy melt is injected in the female die cavity, the oblique face part of the male die body is slowly pressed in, shearing and extruding force is formed in the press-in process, and a magnesium alloy plate can be formed; through shearing and extruding, the compactness of a metallographic structure of the magnesium alloy plate can be effectively improved, and the mechanical performance of the magnesium alloy plate is improved; and design of the die-casting die is advanced, the structure is reasonable and compact, the shearing and extruding force is high, and installing and using are convenient.