This study examines the effects of various lathe turning parameters and cutting conditions on the average surface roughness of super duplex 2507 stainless steel which is predominantly used in oil, gas and petrochemical sectors due to its high strength and corrosion resistance. The machining experiments were conducted on a CNC lathe using Taguchi L9 orthogonal array. The control factors included cutting velocity, feed rate, and depth of cut under dry and flood cooling conditions. Analysis of variance (ANOVA) was used to identify the influence of these lathe turning parameters on average surface roughness. Based on Taguchi design principle, signal-to-noise ratios were calculated. Results from empirical models and Taguchi analysis indicated that feed rate had the most significant effect on average surface roughness (Ra). The optimum values of CNC lathe turning parameters with dry cooling are found to be 47 m/min cutting velocity, 0.05 mm/rev feed rate and 0.15 mm depth of cut. Similarly for wet cutting, these parameters are found to be 94 m/min cutting velocity, 0.05 mm/rev feed rate and 0.05 mm depth of cut. The predicted optimum surface roughness was found to be 0.716 µm and 0.386 µm for dry and wet cutting respectively. The experimental verification showed that the predicted surface roughness has less than 10% differences with actual (experimental) surface roughness values.