To　predict　fatigue　life　under　multiaxial　variable　amplitude　loading　at　high　temperature,　the　stress　amplitude　was　used　as　damage　variable　and　multiaxial　fatigue　damage　was　computed　with　classical　Chaboche　model.　Determination　of　equivalent　stress　under　multiaxial　loading　was　based　on　the　constitutive　relationship　under　uniaxial　loading　and　the　equivalent　stress　was　obtained　with　multiaxial　equivalent　strain.　The　expression　form　of　stress　index　in　the　Chaboche　fatigue　accumulated　damage　model　was　revised.　Fatigue　damage　under　variable　amplitude　loading　was　solved　according　to　the　Chaboche　damage　accumulation　model.　Chaboche　fatigue　damage　cumulative　formula　under　multistage　loading　was　deduced　and　applied　to　fatigue　damage　evaluation　under　variable　amplitude　loading.　The　life　prediction　results　close　to　the　experimental　results.　The　error　is　basic　within　2　time　factors,　indicating　the　feasibility　of　the　life　estimation　method.