The invention discloses a large-strain mold integrating extrusion with C-mode equal channel angular pressing shear deformation. The large-strain mold comprises an upper mold base (7), a male mold fixing plate (9), a guiding rod (5), a male mold (10), a guiding sleeve (4), a front mold core (12), a back mold core (16), a female mold sleeve (13), a cushion block (14) and a lower mold base (2). The large-strain mold is characterized in that a cavity formed in the front mold core (12) and a cavity formed in the back mold core (16) are each composed of four portions, wherein each first portion is a segment of a cylinder, each second portion is a tapered variable-diameter hole, each third portion is composed of three segments of cylindrical equal channels intersecting with one another in sequence, the internal intersection angle formed through intersection of three segments of circular arcs is phi, and each fourth portion is a cylinder convenient for material mold stripping. According to the large-strain mold, the advantages of an extrusion technology and the advantages of an equal channel angular pressing technology are integrated, and efficient, continuous and steady surface levelling and uniform large-strain deformation machining having a high regulating function on crystal orientation can be conducted on a metal material.