Long-term cyclic oxidation resistance is often needed for high temperature alloys used in gas turbine engines for extending their operating lives. This study evaluates the cyclic-oxidation behavior of commercially available Ni-(HAYNES ® 230 ® , 214 ® , HASTELLOY ® X, and HR-160 ® alloys) and Fe-based alloys (HR-120 ® and 556 ® alloys) in flowing air at 982 o C, 1093 o C, and 1149 o C for a total exposure of one year. Test samples were thermally cycled every 30 days at temperature followed by air cooling to room temperature. Alloy performances were assessed by analyzing the weight-change behavior and extent of attack, as measured by metal loss and average internal penetration. The results clearly demonstrated the effects of alloy composition and temperature on long-term cyclic oxidation resistance. The 214 alloy exhibited superior oxidation performance owing to its ability to form and maintain protective alumina scale. Amongst the chromia-formers, 230 alloy performed the best at all temperatures; while Fe-based alloys exhibited rather poor oxidation resistance due to poor scale adhesion. By contrast, the HR-160 alloy showed the lowest weight-loss at 1149 o C of the chromia-forming alloys; however, this alloy underwent extensive internal attack. This study also compared cyclic oxidation resistance of 230, HR-120, and HR-160 alloys in flowing and still air. It was found that alloy composition has a profound effect on the extent of oxidation in flowing air compared to that in still air. For instance, the Fe-based HR-120 alloy exhibited improved performance in flowing air while Ni-based alloys (230 and HR-160 alloys) performed better in still air. The factors that may have influenced the oxidation behavior of alloys in flowing and still air will be discussed.