Abstract: The nano and micro diamond film coated tools was prepared by hot wire CVD method.The surface morphology of the film was characterized by field emission scanning electron microscopy.The prepared CVD diamond coated tools was used to end mill aluminum alloy surface forward and backward at high speed under the condition of dry cutting without lubrication. It studies the characteristics and size of edge burrs during high-speed end milling of aluminum alloy using CVD diamond coated tools. It carries out orthogonal tests on cutting process parameters to explore the cutting parameters and processes with little or no cutting burr when nano-diamonds coated tools are used for high-speed forward milling. The results show that distribution of burrs on the edges of the workpiece is uneven after milling, and the burrs during forward milling are sparse and small in size. Among them, the average height of burrs on the edges during forward milling with nano diamond coated tools is 32.08 μm. Only 46.5% of the forward milling burr height of micrometer diamond coated tools. When nano diamond coated tools are used for high-speed forward milling of flat surfaces, v_c has the greatest impact on edge burrs, followed by v_f, and a_e has the weakest impact. The optimal parameter combination for high-speed milling is a_e=4 mm, v_f=2 000 mm/min, and v_c=400 m/min. The average burr height after milling is 21.29 μm. When the diamond coated tool is used to end mill the aluminum alloy plane, in order to obtain a small burr, the nano diamonds coated tool is selected, the cutting method of forward milling and the corresponding high-speed cutting parameters are adopted.