A mold for molding a green body for manufacturing a zirconium oxide dental implant includes a first molding part and a second molding part. The first and second molding parts each has a first imprinting inner surface and two none-thread inner surfaces for forming the external of the green body with two external thread sections and two none-thread sections. The mold may also include a driving mechanism, a polygonal conical slider and a screw thread forming rod. The polygonal conical slider can be driven for axially sliding into the mold cavity without rotation. The screw thread forming rod is coaxially and slidably penetrated the polygonal conical slider and driven by the driving mechanism for screwing into the mold cavity and unscrewing out of the mold cavity thereby forming the inner of the green body with an internal thread and a polygonal tapering section.