It　is　crucial　to　exactly　predict　the　value　of　C*　in　order　to　predict　creep　crack　growth　and　assess　the　creep　life　of　high　temperature　structures.　The　coefficient　of　h1,　in　the　modified　General　Electric/Electric　Power　Research　Institute　(GE/EPRI)　method　for　power-law　creep　materials　with　a　threshold　stress,　was　determined　in　this　paper　using　the　finite　element　method　for　various　crack　ratios　and　creep　exponents　of　n.　The　effects　that　both　the　threshold　stress　and　the　load　level　have　on　the　values　of　h1　were　also　investigated.　The　results　of　the　study　indicated　that　the　values　of　h1　were　obviously　affected　by　the　threshold　stress　at　a　low　level　of　C*,　but　that　they　remained　almost　constant　with　the　increased　threshold　stress　at　high　levels　of　C*.　The　discrepancy　of　the　value　of　h1　between　the　two　levels　of　C*　increased　as　the　threshold　stress　increased.　©　2019,　©　2019　Informa　UK　Limited,　trading　as　Taylor　&　Francis　Group.