Fatigue tests have been carried out under combined tensile and bending loading on plate specimens containing a surface flaw. The characteristics of fatigue crack growth are studied by a crack-morphological approach. Surface crack growth exhibits two different modes ; “equilibrated growth” and “non-equilibrated growth”. Experimental results are well characterized by the following formulas, a / ( b ⁿ - b ₀ ⁿ ) ^{1/ n} = (0.98+0.07 R _B ) - (0.06 + 0.94 R _B ) · a / h db / dN =C [(Δσ _T +Δσ _B /2) · (π b ) ^1/2] ^m The direct application of Paris formula using numerical solutions of stress intensity factor in semi-elliptical surface crack has not much advantage in precision nor in simplification of analysis.