Extended finite element method is widely used to simulate the discontinuity problems, e.g. fatigue crack growth. This paper mainly analyzes the fatigue crack propagation under elevated temperature in nickel-based super alloy with extended finite element method. Cohesive zone model is used to describe the mechanical behavior around the crack tip. A modified creep damage model is introduced. Fatigue damage and creep damage are accumulated in a linear relationship. And the results produced by computational code are presented and draw a comparison with experimental observation.