DC　XLPE　cables　have　many　advantages　and　are　widely　used　in　power　transmission.　The　problem　of　space　charge　accumulation　in　DC　cables　has　become　the　focus　of　attention.　There　is　a　lack　of　research　on　the　charge　distribution　in　XLPE　under　different　working　conditions.　In　this　paper,　the　space　charge　distribution　in　the　XLPE　under　aging,　temperature　gradient,　and　the　presence　of　bubble　defects　is　studied　and　simulated　in　COMSOL　software　based　on　the　ambipolar　carrier　transport　model.　The　research　results　show　that　the　average　charge　density　increases　by　2.2%　and　6.23%　after　electro-thermal　aging　for　ten　days　and　30　days,　which　is　close　to　the　test　results　in　the　literature.　When　there　is　a　temperature　gradient　in　XLPE,　the　charge　density　on　the　side　with　higher　temperature　is　more　significant　than　that　on　the　side　with　lower　temperature,　and　the　higher　the　temperature,　the　greater　the　mobility,　resulting　in　deeper　charge　injection　depth.　When　there　is　a　bubble　defect,　a　＇recessed　area＇of　charges　is　formed　in　the　bubble,　the　charge　density　in　the　bubble　is　lower　than　that　of　the　surrounding　XLPE,　and　the　charge　accumulation　at　the　interface　between　the　bubble　and　XLPE　is　evident.　The　research　results　will　provide　a　specific　basis　for　the　safe　operation　of　DC　XLPE　cables.　©　2022　IEEE.