Based on the processing properties of the different electrode materials, a hollow cylindrical graphite electrode was used to conduct high-speed arc discharge machining on the ultra-hard and ultra-hard cutting materials,such as nickel base superalloy GH4169. The experimental results show that the hollow cylindrical graphite electrode can achieve relatively optimal material removal rate and surface quality under gas-liquid mixing medium (gas 0.3 MPa, liquid 0.1 MPa), when voltage is 25 V, duty ratio is 50% and frequency is 500 Hz, and the electrode loss is also relatively little. At the same time in order to avoid occurring short circuit phenomenon in a process,PCI1716 data acquisition board was used as hardware platform on the basis of the highspeed data acquisition system. with the Advantech 32-bit DLL driver interface, the Borland Delphi 7.0 Pascal language was used to hardware drive and control, which realized real-time monitoring of current signal in short arc machining.