When titanium alloy Ti-6Al-4V is cut at high speed,a layer of oxide film can be formed on the processing surface,which affects the mechanical properties of titanium alloy.The single factor cutting experiment for titanium alloy Ti-6Al-4V was carried out.The deformation characteristics and phase compositions of the cutting surface were studied.The results show that the plastic deformation of the cutting surface is serious,the thickness of the deformation layer increases with the increase of feed rates,and the oxidation reaction occurs on the cutting surface,oxide films with different colors are formed on the surface,the composition of which is mainly Al2O3,anatase TiO2 and rutile TiO2.