Abstract: In this paper, a double arm charge-discharge circuit is described. A high repetition-rate high voltage and variable width rectangular pulse has been obtained. Its technical data are as follows: Its amplitude is 600 V-8 kV continuously adjustable; The maximum repetition-rate is 30kHz; The rise and fall time is less then 1.5s when the load capacity is 56 pF, less then 1.8s when the load capacity is 112 pF; The pulse duration ratio is 1:10-1:1 continuously adjustable. Theoretical analysis for the circuit, has been made.