Dry electrostatic cooling (DESC) assisted machining is one of the green machining technologies that uses ionized air flow as lubricating and cooling medium in the machining process. The influence of discharge parameters on the efficiency of ion transport and ozone concentration in the DESC is experimentally researched. The results show that the efficiency of ion transport increases with the rising of the discharge current and air pressure, but decreases with the rising of the distance from the nozzle and the nozzle diameter. The tungsten electrode is used to obtain high ozone concentration with the nozzle diameter of 2-4mm, air pressure of 0.2-0.4MPa, and the distance from the nozzle within 0.5mm. Experimental research on the DESC assisted machining for hardened steel GCr15 shows that cutting force decreases by 7%-28%, tool wear reduces by 30-50%, and tool life is 1.5-3.3 times more than dry cutting. Better results are achieved when increasing the cutting speed.