The effects of Aluminum addition on the oxidation behavior of CM-247LC Nickel base superalloy were investigated under high temperature isothermal oxidation test at 1000°C in the dry air. In this study, we explored the difference and observed the micro-structure of oxides, gamma matrix as well as gamma prime precipitate, and further studied the impact of high temperature oxidation behavior and phase stability analysis. Results showed that by adding small amount of Al in CM-247LC superalloy, protective oxides could form more easily, and a more regular morphology of gamma prime in the base material microstructure could be retained, which in-directly reduced the rate of outward diffusion and prevented further oxidation.