The ANSYS finite element software is used to established a single-layer multi-trace stress field model by thermal-structural indirect coupling method, and the stress field of AlSi10Mg fabricated by selective laser melting is simulated. The distribution and evolution of internal stress and the influence of different exposure times and point distances on residual stress are analyzed. It is found that after the temperature is homogenized, the residual stress in overlap region of molten pool is high (the highest residual stress), and the residual stress in the central region is low (the lowest residual stress). As ET and PD increase, the maximum residual stress gradually increases. However, by further increasing PD, the formation of defects leads to a decrease in stress. As the ET increases and the PD decreases, the minimum residual stress increases.