The utility model relates to a mold unit for cutting framework in a lead pin connecting position of a semiconductor encapsulation unit. The mold unit consists of a punching male mold and a punching female mold, and is structurally characterized in that the punching male mold consists of punching male mold cutting edges and a male mold body, the shape of the punching male mold cutting edge part is a symmetrical inwards concave crescent shape, the punching male mold cutting edges are symmetrically distributed on the edge of the upper surface of a female mold body in the length direction of the upper surface of the male mold body, a threaded hole is formed in the back side of the male mold body, the punching female mold consists of punching female mold cutting edges, female mold cutting edge convex blocks, waste material through holes and a punching female mold body, the female mold cutting edge convex blocks are symmetrically distributed in the edge of the upper surface of the punching female mold body in the length direction of the upper surface of the punching female mold body, the punching female mold cutting edges are positioned at the upper surfaces of the female mold cutting edge convex blocks, the waste material through holes are positioned under the punching female mold cutting edges and penetrate through the female mold cutting edge convex blocks and the punching female mold body, and the geometric dimension of each waste material through hole is a little greater than that of each punching female mold cutting edge, so that waste materials can be conveniently discharged.