Abstract: A feedback control corcuit is presented to solve the problem of electric isolation between the input and output of high voltage feedback circuit used in the ESA of fuze. Sampling voltage from the original side of high voltage transformer can control the charge voltage of high voltage capacitance and solve the problem of electric isolation, and adopting filter to solve the problem of spike voltage in high voltage transformer. Simulation experiment results showed that the voltage of capacitance could be controlled to 2kV, the input and output of high voltage transformer was effectively isolated and the control circuit worked reliably.