When turning titanium alloys, the high temperature in the processing zone reduces the surface quality and intensifies the wear of diamond turning tools. Cooling methods such as atomized nano-fluid injection are used to improve the turning environment, improve the processing quality of titanium alloy surface and the durability of diamond cutting tools. A Ti-6Al-4V titanium alloy material model was established based on ABAQUS simulation software. The temperature variation of chips and tools under different cooling modes was studied, and the simulation results were verified by turning experiments of titanium alloy. The results show that the cooling effect of atomized nano-fluid injection is good when turning titanium alloy. The maximum surface temperatures of chips and tools are 168 ℃ and 142 ℃, respectively, which is about 68% lower than that of common cooling mode. The simulation and experimental results of chips and tools under stable cutting state have errors within 5%, which verifies the rationality of the simulation results.