In order to study the notch effect on rotating bending fatigue properties for SUS403 stainless steel, the rotating bending fatigue tests were carried out at room temperature, 300°C and 600°C with a frequency of 1200 cycles/min. The temperature dependence of fatigue limit and the estimation method of fatigue notch factor were investigated. The relationships between the fatigue limit σW of smooth specimen and the tensile strength σB and also σW and the Vickers hardness HV were obtained as σW=0.58σB=1.63 HV at every temperature. Furthermore the relationship between the parameter (β-1) √σ0/σB and Kt-1 was proposed to estimate the fatigue notch factor, where σ0 is the tensile strength at room temperature, β is the fatigue notch factor at a certain temperature and Kt is the stress concentration factor. Then fatigue notch sensitivity factor η was obtained as η=0.056√σB/Kt. Using these results, the estimated fatigue limit was satisfactory and the predicted accuracy was ±10%.