Components of gas turbines must be extremely resistant to high temperatures, high stresses, high-temperature corrosion, and erosive environments. The materials used in these environmental conditions are mainly cobalt-based superalloys. In this study, the low-cycle fatigue of the cobalt-based superalloy FSX-414 was examined. The total strain range of a gas turbine between 760 ℃ and 870 ℃ was considered as the parameter representing the actual gas turbine operation. In addition, tests were performed using a trapezoidal waveform of the total strain to reflect the operation-stop conditions of a gas turbine with frequent shutdowns. The results of the fatigue test were compared with the Coffin–Manson method and energy methods. The fractured surface was analyzed using a scanning electron microscope (SEM).