To solve the problems of machining composite components, such as narrow space, poor accessibility and low accuracy, electroplated diamond abrasives are used to spirally drill the material at low stiffness based on micro-edge cutting principle. Theoretical analysis on cutting length of abrasive and comparative test show that the cutting force of diamond tools is generally lower than 60 N, that the maximum of which is 30% lower than that of ordinary cemented carbide tools; and that there is no bur nor burn on the edge drilled by diamond tools. In conclusion, micro-edge cutting could decrease the force and burs, thus improving accuracy.