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A stereophotogrammetrical analysis in SEM is used to investigate thefracture morphology of the high-strength low-alloy steel generated under combinedbending-torsion fatigue loading. Changes in many roughness parameters are presentedfor two series of profiles parallel and perpendicular to the local crack propagationdirection in dependence on both the fatigue life and the loading ratio r= τa /(τa+ σa) (σais the bending amplitude and τa is the torsion amplitude). Profile’s fractal parametersare also calculated as “scale-independent” characteristics. Statistical distributions offacet angles with respect to the horizontal plane revealed prevailing orientations oflocal crack growth directions in various mixed-mode loading cases. One of theinteresting results is that many roughness parameters start to increase rapidly above acritical value of loading ratio rc ≈ 0.5.