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A thermodynamic coupling finite element model of tungsten selective laser melting was established by using the ‘birth and death element’ technique to simulate the powder laying process, taking into account the material parameter characteristics and latent heat of phase transition. The temperature and stress fields of the forming parts during selective laser melting were simulated. The effects of different preheating temperatures of substrate and different support structures on the residual stress of formed parts was investigated. The simulation results show that tungsten has undergone many heating and cooling processes during selective laser melting, and the temperature distribution is not uniform. Both substrate preheating and applying support structures can reduce the residual stress of the formed part. When the preheating temperature of the substrate is 1273.15K, the residual stress of the intermediate joint of the forming part is reduced by 118.99MPa (9.96%). When the four-layer grid support structure is adopted, the residual stress of the middle joint of the forming part is reduced by 413.33MPa (34.61).