After manufacturing, surface quality varies according to the type of manufacturing and cutting parameters. In this study, surface roughness measurements were performed after turning AISI 308 stainless steel in different machining parameters. Test samples prepared from steel in diameter 40 mm, length 200 mm were processed in CNC lathe machine in different cutting parameters. The highest roughness values were used for calculating the cross-sectional areas between the peak-valley points on surface profile. Using these roughness profile area values, theoretical fatigue life was calculated and evaluated due to the surface roughness. As a result, surface roughness tends to decrease with increasing cutting speed and theoretical fatigue life values have increased. The surface roughness has increased with the feed rate and fatigue life limit values have decreased. (C) 2019 Elsevier Ltd. All rights reserved. Selection and/or Peer-review under responsibility of International Conference on Modern Trends in Manufacturing Technologies and Equipment 2018: Materials Science.