The effect of substrate preheating process on the residual stress, microstructure, and tensile property of GH4169 alloy samples repaired by laser deposition is studied. The results show that when the substrate is preheated to 300 ℃, as for the GH4169 alloy sample, the average decrease in amplitude of the residual stress along x direction (σx) is 59.4 MPa, which is reduced by 11.7%. The average decrease in amplitude of σy along y direction is 189.7 MPa, which is reduced by 44.6%. The Laves phase of the interdendritic precipitation in deposition layers presents a granular fragmentation phenomenon. Both the tensile strength and yield strength are basically equivalent to those of repaired samples without preheating, and the elongation rate is 12.3%, which is a onefold increase. These indicate the standard of forging is reached. The experimental results indicate that substrate preheating can effectively improve the tensile property of GH4169 alloys repaired by laser deposition at room temperature.