The evolution of corrosion products and their influence on the fretting wear behavior of GH4169 alloy in a CO 2 with 0.5% SO 2 at 800 °C was investigated. The corrosion behavior increased the sensitivity of GH4169 alloy to the displacement amplitude of fretting wear. At low displacement amplitudes, a dense and high-hardness Cr-rich oxide film effectively isolated the contact interface and enhanced wear resistance. At high displacement amplitudes, the Cr-rich oxide film ruptured and exposed the underlying Cr-depletion zone. Discontinuous Al 2O 3 internal oxide particles induced microcracks at stress concentration sites. Sulfidation behavior induced interfacial failure and activated third-body wear, which continuously aggravated material degradation.