In the process of laser cladding, local heat input causes uneven temperature distribution and then produces thermal stress. The large temperature gradient in the melted-solidified region causes uneven plastic deformation due to solid-liquid phase change. In the study, based on the different types of heat source, the numerical models of single-layer and multi-layer laser cladding on single channel were established in virtue of the transient thermal-mechanical coupling analysis method. The three-dimensional residual stress fields of specific paths were established.