The notch effects on the fatigue strength of welded joints are both stress concentration and fatigue strength reduction. In the notch stress approach, the notch effects are usually approximated by introducing weld-bead parameters for the local detailed weld joints. In this paper, well-known notch stress approaches -critical distance method, area method and fictitious rounding method are presented for the fatigue strength of cruciform joints. The estimated results of the present methods are applied to the experiments performed in this study and reported in the references. The results of the application show that the fatigue-life scatterness of the experimental data expressed in the nominal stress is significantly reduced by introducing the effective fatigue stress of the present study. ※Keywords: Notch stress analysis(노치응력해석), Fatigue effective notch stress(유효노치피로응 력), Fatigue strength of cruciform joints(십자형 용접 연결부 피로 강도)