Abstract: Three coaxial peaking-chopping subnanosecond gas switches were designed,including two ring-ring electrodes and a sphere-ring electrode. Experimental researches on their operating characteristics were performed on a semiconductor opening switch-based pulse source respectively. Results show that the switch can work steadily at 1～500 Hz repetition rate, and can output a pulse with 400 ps rise time, 320 ps fall time, 460 ps width and 129.2 kV peak voltage, as the switch adopts the ring-ring electrodeⅡ. It is also revealed that gap size, gap pressure and repetition rate of the switches all have great effects on rise time, fall time, voltage range and repetition rate of output pulses. The subnanosecond gas switch has excellent operating characteristics when it operates at small gap (1～2 mm)