The present invention provides a method and system for finding the resonant frequency point of a transducer. The method includes the following steps that: S1, the minimum operating frequency and maximum operating frequency of the transducer are obtained; S2, a resonant frequency point preset value is set, a hop-up interval is formed with the maximum operating frequency and the resonant frequency point preset value, and a hop-down interval is formed with the resonant frequency point preset value and the minimum operating frequency; S3, if the current phase of the transducer exceeds the voltagephase of the transducer, a current interval hops to the hop-up interval, otherwise, the current interval hops to the hop-down interval; S4, a new hop-up interval and a new hop-down interval are formedwith two end point values of the current hop-up interval or current hop-down interval and corresponding intermediate point frequencies; and S5, if the current phase exceeds the voltage phase, a current interval hops to the new hop-up interval, otherwise, the current interval hops to the new hop-down interval, and the step S4 and step S5 are repeated, and the frequency of the transducer when the current phase and the voltage phase are the same is adopted as a resonance frequency point. With the method and system of the present invention adopted, the number of the times of finding can be greatly reduced through frequency hopping.