Abstract: By analyzing the microstructural evolution and creep of NASAIR100 at different stresses in several high temperatures,four dominating parameters of microstructural evolution as well as its relationship with creep curves were found out. While the change of precipitate's thickness and interlamellar spacing during rafting was considered,a microstructural evolution model was established based on the primary rafting model,the deformation process of precipitation,the matrix and the creep curves was obtained. By comparing with the tests,the influence of different microstructural evolution processes on creep curves was given,showing that,if four parameters' change in microstructural evolution at high temperature is considered,the model can simulate the creep of material at different stresses and temperatures preferably and more close to the reality.