There is a tendency to generalize that the fatigue strength at 10＾7-10＾8 cycles in high cycle fatigue increases linearly with tensile strength, but it is not known in low cycle fatigue. This study was down to investigate the relationship between the static strength and the fatigue strength in low cycle range depending on the behavior of fatigue crack growth. In this experiment, it was shown that the fatigue strength in low cycle range also varies directly with static strength on SM45C steel.