For proper fitness of a core portion of an abutment to a patient, a wax model base for an abutment of a dental implant includes an engagement portion 1 engaging with an implant fixture analog embedded in a gypsum model without rotation, a truncated conical portion 2, a building portion 4 provided directly on an inner peripheral edge of a ring-like first stepped portion 3, which is provided on an oral cavity inner side of the truncated conical portion 2, or through a cylindrical portion 4a having a low height to have a conical shape expanding toward the oral cavity inner side and have a cutoff portion 5 on an outer peripheral surface, a cylindrical portion 7 provided on an inner peripheral edge of a ring-like second stepped portion 6 provided on the building portion 4, and a screw hole 8 along a center axis of the base.