Method of making sintered object

In order for a surface of a three-dimensional sintered object to be smoothly finished by removing unwanted portions and an excessively sintered growth formed during sintering to form sintered layers, the three-dimensional sintered object is formed by repeating successive processes of dispensing a powdery material and directing an optical sintering beam to the powdery material to form the sintered layer, until a required number of integral laminated bodies are formed. During the formation of the integral laminated bodies, trimming is applied to a first zone different from a second zone in which each laminated body is formed, to remove unwanted portions of the respective laminated body.