The present investigation is undertaken to make a decision on parametric optimization of multiresponses such as metal cutting of material removal rate during machining hardened cast iron steel using mild carbon steel under normal environment through grey relational analysis combined with Taguchi method. Also predicted mathematical models of 2nd order have been developed for responses and checked for their accuracy. The second-order mathematical model presented a higher R2 value and represents the best fit of the model. The model indicates good correlations between the experimental and predicted results. The proposed grey-based Taguchi methodology has been proved to be efficient for solving multi-attribute decision-making problems as a metal cutting in a turning machine.