Affected by the very fast transients overvoltage( VFTO),the acquisition card of active electronic voltage transformer in the gas insulated substation ( GIS) might be damaged while the circuit breaker is being operated. In order to solve this problem,a new impedance suppressing method for the electronic voltage transformer has been proposed in this paper. Through amplitude-frequency characteristic analysis,we deduced the amplitude of very fast transient overvoltage for the electronic acquisition card,the multilayer coaxial capacitors in parallel structure is proposed to increase the capacitance of low voltage arm capacitor, which also increases high frequency voltage division ratio and effectively suppresses the VFTO secondary overvoltage. At last, the simulation results show that the method can significantly reduce the VFTO secondary voltage output, thus it protects the collector from high voltage and improve operating stability of electronic transformer.