The present invention relates to the field of zipper technology, in particular, it relates to a manufacture process of three-point grain metal zipper and its forming die. It is characterized by that said invention adopts a step-by-step type die-arranging mode, utilizes one machine to implement positioning directional blanking and stepped processing of metal flat wire and obtain specific form, andutilizes the change of thickness of metal copper or aluminium wire and correspondent tooth profile height to manufacture light-load, middle-load and heavy load zippers. Besides, said invention can utilize the change of form of metal copper wire or aluminium wire to make the original rectangular tooth be changed into the trapezoidal tooth, and can manufacture single-tooth structure having reinforced dovetail or having no dovetail according to the requirement and application.