Abstract: A simplified three-dimensional model of the shell and tube heat exchanger was established. The temperature field and stress field of this structure were calculated by finite element software ANSYS. The stress field after 1 hour and 105 hours were compared, and the simulation result of high temperature creep was analyzed. Results demonstrate that the maximum equivalent stress descended obviously compared with that after 1 hour and its location was changed due to stress relaxation caused by the creep deformation. The maximum creep strain of the heat exchanger at 105 hour reached 0.337; the serious creep deformation occurred at the top of shell cover and middle part of cylinder, consistent with failure position in the literature, which proved the accuracy of the simulation results.