Abstract: It is proved circcular that ω_0 is equal to ω_1ω_2~(1/2) in this article. Where ω_0 is theintrinsic resonant frequency in a series connected resonant circuit which consists ofcapacity C of a pulse condenser and its parasitic inductance L. The ω_1 and ω_2 isclose to ω_0 and it is necessary to satisfy the following formulae, ω_1<ω_0<ω_2 aswell as |ω_1L--(ω_1C)~(-1)| =|ω_2L--(ω_2C)~(-1)|. It is more reliable to measure theparasitic inductance in a pulse condenser by means of this method, since no othercomponents appear in the circuit.