The paper describes the procedure to obtain the machining conditions for turning operation considering unit cost of production as an objective function. The optimality conditions for single point cutting operations are determined based on the objective function using dynamic programming technique. The optimal policy of machining conditions are determined for evolution of minimum cost considering the important cost related machining criteria such as actual machining time, tool reuse time, set up time, tool life, and tool changing time. The mathematical models are also developed considering the Krononberg's data used for standard turning operation. The effects of different constraints on the objective functions are analyzed through various graphical representations. In this study, the Taguchi method a powerful tool for experiment design is also used to optimize the cutting parameters to achieve better surface finish and to identify the most effective parameter for cost evolution during turning. Taking significant cutting parameters into consideration and using multiple linear regressions, mathematical model relating to the surface roughness height R a is established to investigate the influence of cutting parameters during turning. The developed optimality condition affects the economics of machining conditions. The graphical representations also help to understand and analyze the effects of various input constraints at the optimum point and their significant influences on production cost. The analysis can propose an effective methodology in advance for proper setting of machining parameters in practice, which may reduce the cost of unit production.