Accelerated　degradation　test　is　one　of　the　commonly　used　reliability　test　methods　for　power　semiconductor　devices.　Its　principle　is　to　implement　the　working　conditions　of　the　devices　that　exceed　normal　strength　based　on　scientific　theoretical　derivation　and　the　device＇s　thermoelectric　model,　thereby　changing　the　aging　environment　of　the　devices　during　test　to　analyze　the　degradation　of　device＇s　parameters.　In　accelerated　degradation　test,　one　of　the　commonly　used　methods　is　to　change　the　working　junction　temperature　of　the　device　through　the　constant　current　test.　IGBT　as　a　high-power　electronic　device,　its　working　condition　is　usually　a　large　current　or　voltage,　which　will　cause　the　device　to　have　an　high　junction　temperature,　and　this　situation　will　lead　to　device　damage.　The　research　content　of　this　paper　is　mainly　aim　at　the　IGBT　device　in　the　accelerated　degradation　test,　and　a　more　accurate　junction　temperature　measurement　method　is　proposed　than　traditional　methods.　©　2020　IEEE.