To examine the effects of the surface finish and defects on fatigue limit, specimens differently finished, i. e., sand paper (Grade #600, #80) finish and electrolytic polish, were prepared. Moreover, to simulate surface defects, a small artificial hole of which diameter is varied from 40 to 200 μm is introduced on the specimen surface. Both as-received and annealed specimens were applied so as to extract the effect of the work-hardened surface layer on the fatigue limit. Through examination of the fatigue limit and ten non-propagating crack the following results are obtained: (1) the surface roughness slightly influences the fatigue limit, while the work-hardened surface layer has a primary effect on the fatigue limit. (2) An increase in the diameter of the small hole decreases the fatigue limit and results in the prolongation of the non-propagating crack. (3) For the non-propagating crack, the threshold stress intensity factor range ΔKth decreases with a decrease in the crack length.