This document summarizes an experiment to optimize machining parameters in a turning operation of flyash composite material to minimize surface roughness using Taguchi methodology. The experiment was conducted with three factors (work material, speed, depth of cut) at three levels each in an L9 orthogonal array, with surface roughness measured as the response. Analysis found depth of cut to be the most significant factor, followed by speed and work material. The optimal settings to minimize surface roughness were found to be a work material of aluminium-flyash composite with 6% flyash, a speed of 878 RPM, and a depth of cut of 0.5mm.