This paper is aimed at investigating the damage and remaining life of a whole HP-Nb hydrogen reformer tube serviced for 12 years. The damage and remaining life evaluation of different parts of the tube were made using metallographic examination, ambient and high temperature uniaxial tensile tests, creep rupture tests and damage mechanics analysis. The results showed that different parts of the tube have the different damage and remaining life due to different service temperature, higher the service temperature, severer the damage and shorter the remaining life. Based on these research results, a case of local maintenance of the reformer tube was introduced.