The paper is concerned with the effect of cutting parameters on surface microstructure of titanium alloy TC17 in high speed milling with the carbide cutting tools by single factor experiment. It will be provided experimental evidence for optimization cutting parameters and surface quality control of titanium alloy parts in high-speed cutting process. It is observing microstructure with Germany's Leica DMI 5000M inverted metallurgical microscope. The results show that in the range of experimental parameters, the effect of milling speed, feed per tooth and milling depth on surface microstructure in high-speed milling of titanium alloy TC17 is little. There is no obvious phase change, as indicating that most of the heat generated by chip away, little heat incoming workpiece, under the conditions of high speed milling titanium alloy TC17.