The use of CNC lathe in the processing process,often encounter dimensional accuracy instability,position accuracy instability,surface roughness instability and other product quality is difficult to control prob-lems,and even encounter unknown reasons of vibrating tool,broken tool,debris,parts deformation and other problems,this paper mainly from three major aspects of CNC lathe processing product quality control methods,CNC lathe equipment,Process method,tool bar,blade selection and cutting parameters.