Based on Abaqus code, a nonlinear finite element method is developed to simulate temperature field and stress distribution in 718 alloy induced by laser cladding. According to the characteristics of laser cladding, a moving heat source model is established through developing a user subroutines in Abaqus code. Temperature and residual stress fields in single-channel monolayer cladding, single-channel double layers cladding and singlechannel ten layers cladding are calculated using the developed computational approach. The features of temperature field and the formation of stress are investigated numerically. The results obtained from this research are helpful in deeply understanding mechanism of metallurgical defects such as hot cracking and are also beneficial for finding measures to prevent the occurrence of these defects.