The objective of this paper is focused on turning of AISI D3 Steel using coated cemented carbide tool cutting inserts. The experiments were performed on a KIROLOSKAR model center lathe using three input cutting parameters, cutting speed, feed and depth of cut. Hardened steels are most widely used in multifarious industrial applications like tool design and mould design. The output responses measured were surface roughness (Ra), Interface temperature and material removal rate (MRR). In present study, the Taguchi technique has been used to optimize the controllable process parameters for AISI D3 cold work turning tools then the interaction effects of various hard turning parameters on each response were also studied using analysis of variance (ANOVA) and interaction plots. Further a regression is modelled as a function of cutting parameters to predict values for surface roughness in comparison with experimental values within reasonable limits. Based on the main effects plots and signal to noise ratio (S/N) obtained through Taguchi’s approach, were used to relate the optimum level for surface roughness chosen from the considered there levels of cutting parameters.