Crater wear is defined as the deformation of the rake face of cutting tool. Craters created on the rake face always lead to the removal of the materials from the cutting edge. The diffusion wear of a cutting tool causes the tool life to be shorter and the surface roughness of workpiece to be more irregular. This in turn results in a higher manufacturing cost and a lower quality product outcome. This project is aimed to study the effect of the crater wear on the tool life and the surface roughness of workpiece in turning process.