The paper deals with the end-milling machinability of α-β titanium alloy (Ti-6AI-4V alloy) by new PCD (Polycrystal-line Diamond) cutting tools at high cutting speeds in order to develop a new technology for a high productivity titanium finishing. The main focus of this paper is on investigating the relationships among cutting conditions, PCD tool materials, and tool wear. It was found that the edge engagement time of cutting tools with titanium workpiece has a great effect on PCD tool wear. Compared to cemented carbide tools, PCD tools have a longer tool life, especially at higher cutting speeds. The geometric shape of cutting edges and tool material greatly influences the performance of PCD tools in cutting titanium alloy.