The laser sintering device includes a laser sintering head configured to output a laser beam toward a material to be sintered on a device to be sintered, so as to sinter the material to be sintered, and a heating unit configured to, prior to and/or subsequent to sintering the material with the laser sintering head, heating the material to be sintered and/or the sintered material. The material to be sintered is preheated by the heating unit prior to sintering the material to be sintered, and/or the sintered material is annealed by the heating unit subsequent to sintering the material to be sintered, so as to reduce a difference between a temperature before the sintering and a temperature during the sintering, and/or reduce a cooling rate after the sintering, thereby to reduce a shrinkage stress applied to the material to be sintered and the device to be sintered.