A molding method of a 3D object including the following steps is provided. A 3D point data of a 3D object is obtained to acquire a first 3D digital model. The first 3D digital model is magnified according to a first ratio to acquire a second 3D digital model, wherein the second 3D digital model has a profile and the profiles may be divided into a plurality of sub-profiles. The sintering light source emits a light beam. The light beam sinters a first molding material according to the sub-profiles to form a plurality of molds correspondingly. A second molding material is filled between the molds and the molds are assembled to make the second molding material filled between the molds to form a green body. The green body is heated to form the 3D object.一種三維實體的成型方法,其包括以下步驟:取得三維實體的三維點資料,以獲得第一三維數位模型;使第一三維數位模型依第一倍率放大而獲得第二三維數位模型,其中第二三維數位模型具有輪廓,且輪廓區分為多個子輪廓;利用燒結用光源發出光束,使光束依據這些子輪廓燒結第一成型材料以對應形成多個模具;填入第二成型材料於這些模具之間,並組立這些模具,使得填充於這些模具之間的第二成型材料形成坯體;加熱坯體以形成三維實體。1a‧‧‧坯體71‧‧‧第二成型材料80‧‧‧母模82‧‧‧開口90‧‧‧公模
