The performance of carbide cutting tool in end milling cast iron FC 250 in dry conditions and when using the cutting fluid has been carried out with emphasis on mechanisms of wear experienced by the cutting edge. In addition, the effects of other milling parameters were studied; cutting speed (m/min), axial depth of cut (mm) and feed rate (mm/tooth). Results indicate failure of the cutting edge is dependent on the parameters mentioned above. In dry machining, wear mechanisms were caused by adhesion and micro-attrition at low combination of machining parameters. While at high combination of machining parameters, the cutting edge failed due to catastrophic failure such as micro-cracks. Wear mechanisms that occur when milling using cutting fluid were abrasion, adhesion and diffusion. Longer tool life was achieved when using cutting fluid, i.e. about double compared to dry cutting at the optimum milling conditions. Water-based fluid was found to be better than the high viscosity oil to increase the tool life of the cutting tool.