A full denture base manufacturing method is provided that can easily manufacture a full denture base, using a set of maxillary impression tray and a mandibular impression tray for taking an impression from a patient including an edentulous patient.An impression material is applied on each of a maxillary impression tray 3 and a mandibular impression tray 4 configuring a set of impression trays, and respectively having a U-shaped groove, the U-shaped groove having a front surface side on which the impression material is to be applied and being provided with projecting parts 1 on a back surface side thereof, and the applied impression material is pressed against an alveolar ridge within an oral cavity and set, to determine bite position and height in a state in which at least a part of flat top surfaces of the projecting parts 1 contact each other, the second impression material is applied between back surfaces of the impression trays 3, 4 and set in a state in which at least a part of the flat top surfaces contact each other, each of the impression trays 3, 4 and the impression material are removed from within the oral cavity in one piece of the maxillary and mandibular impression trays, or separately in two pieces of the maxillary and mandibular impression trays, and a model material is thereafter injected to each impression material on the removed maxillary and mandibular impression trays and set, in order to manufacture an edentulous jaw model, and the edentulous jaw model is set on an articulator in a state in which the bite position and height that are determined in advance are reflected, in order to manufacture a full denture base.