Abstract: On the working principle of the high frequency oscillator for arc ignition,the circuit model of the high frequency oscillator is set up in this paper.After the mathematic analysis of the model, the waveform functions in the instantaneous process of the current and voltage are obtained.Based on the real condition, these functions are analyzed deeply in the review.In order to improve the effect of arc ignition of high frequency oscillator,the problems of relationship among the parameters and parameters definition in the circuit are discussed on the result of the mathematical analysis.Some significative conclusions and calculation functions of the circuit parameters are reached.Those supply theoretical foundation to a certain extent for the design and debugging of the high frequency oscillator.