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A notch in a structural component can easily provoke the initiation andgrowth of a surface crack because of stress concentration. The stress field for thiscomponent can be rather different from that found out in an unnotched component withan identical surface flaw, and fatigue life may heavily be affected by such a geometricdiscontinuity. In the present paper, the influence of a circular-arc circumferential notchin a round bar is analysed. Firstly, the Stress Concentration Factor (SCF) related totension loading is determined. Then, an elliptical-arc external surface flaw is assumedto exist at the notch root, and the Stress Intensity Factor (SIF) along the crack front iscomputed through a finite element analysis for both tension and bending, by varying thestress concentration factor from 1.0 (smooth bar) to about 3.0 (small notch radius). Theeffect of the stress concentration on the SIF values is discussed for the considered crackconfigurations. Finally, the surface crack propagation under cyclic loading is examinedthrough a numerical procedure which takes into account the computed SIF values.