The paper calculates and analyses the temper ature field and the stress field of high pressure rotor ( H. P. R) of domestic 200 MW intermediate reheat turbine during the staro- up of the intermediate pressure cylinder ( I. P. C) by adopt ing the finite element method, and estimates the loss in t he serv ice lifetime of the H. P. R in course of the I. P. C start- up on its once run. The r esults are useful fo r optimizing the start-up mode of this type of turbine unit.