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The fatigue crack growth under mixed mode condition has been discussed within the scope of linear fracture mechanics such as maximum tangential stress, maximum tangential principal stress and minimum strain energy density. The purpose of this study is to investigate the characteristics of fatigue crack growth in 304 stainless steel under mixed mode. The fatigue test results carried out by using inclined pre-crack specimens was compared to both of the theoretical predictions of the criteria, maximum tangential stress and strain energy density. As difference from theoretical analysis, the transition region from mixed mode to mode I appeared in the fatigue test. There is deep relationship between the angle of slanted pre-crack and transition. Therefore, as applying the different stress intensity factor to each mode I+II and mode I, the directions and rates of fatigue crack growth are evaluated more accurately under mixed mode.