Abstract: Based on multi-factor orthogonal cutting tests, the present paper is to research for the regulations of the influences of work material, cutting speed and tool rake upon ths wear resistance of coated and uncoated carbide tools. Some essential rules for the application of coated carbide tools are proposed, and a typical example is chosen to show the optimization of the cutting conditions of a coated carbide tool.The research method of multi-factor orthogonal test and the discussion about the microcomputer aided optimization of cutting condition would be beneficial for solving similar problems.