The processing of deep and small holes with super large depth-to-diameter ratio has always been a difficult problem in the manufacturing industry. For small hole EDM drill machine, it is more difficult to process deep and small holes with a depth-to-diameter ratio of more than 100:1, especially those with a diameter of less than 1.0 mm. EDM deep and small hole machining is one of the more mature machining methods. Through a series of experiments (tests on brass/copper electrode tube), this paper expounds the feasibility of electric machining deep holes, making it possible to electric machining deep small holes and guaranteeing certain technical conditions.