To provide a method for producing a molding die whose production period can be remarkably reduced, and further having improved strength and durability, and, whose production is easy, and which is also economically advantageous, and to provide a master model thereof.

The method for producing a molding die comprises: a stage where an object model 20 is prepared; a stage where the object model is mounted freely removably, so as to create a master model 30; a stage where a pattern 41 for a cavity die essentially consisting of a zinc alloy and the master model 30 are matched, a metal resin is injected from a resin injection part 44 into a space 43 forming a die face part, so as to create a cavity die 40; and a stage where the object model is arranged at the die face part 49 of the cavity die, thereafter, the cavity die and the pattern 51 for a core die essentially consisting of a zinc alloy are matched, and a metal resin is injected from a resin injection part 54 of the pattern for a core die into a space 53 for forming a die face part, so as to create a core die 50.