Abstract: The creep behavior of 30CrZMoV steel of rotor at high temperature was studied experimentally. Based on existing creep theory and the spline function collocation method, an algorithm was developed to calculate the transient creep strain and stress of a rotor of steam turbine to be straightened. The transient creep displacement, the residual bending value and the residual stress after unloading were also predicted by the software. The numerical results show that the present method is reasonable and helpful in providing guidelines on defining loading and heating scheme for the creep straightening of rotors.