Abstract: Post-weld heat treatment（PWHT） is an important process in fabrication of pressure equipment,and is one of the weakest links,has the characteristics of integral,one-time and finality. Pressure equipment post-weld heat treatment is not standard at present,most company operating only on their experiences,there is no proper evaluation of overall effectiveness on PWHT,it has left safety hidden trouble for pressure equipment,therefore the boiler pressure vessel standardization committee will implement safety registration system for PWHT,try to make it rise from perceptual stage to rational stage.