The fatigue testing of the specimen with a central open hole was carried out to investigate the influence of the surface roughness on the fatigue lifetime. Fracture morphology investigations were used by scanning electron microscope. The reliability analysis of the specimen was carried out by detail fatigue rating. The results revealed that the less the roughness is, the longer the fatigue life of open hole and the higher the value of DFR (Detail Fatigue Rating) is. Under the same technological conditions, the effect of corner crack on fatigue life of open holes is greater than the effect of internal crack. So, the effect of a decrease of roughness on the fatigue life of an open hole is similar to a change of crack type from a corner crack to an internal crack.