Abstract: To explore a more convenient measurement of focused ultrasound power, piezoelectric ceramic plate was used to receive ultrasonic signal directly. Due to an acoustic force acting on the surface of piezoelectric ceramic plate,by means of electromechanical analogy, the transient response was obtained, which was composed of voltage response caused by forced vibration and high frequency attenuation response caused by natural vibration,then the conversion relationship between output signal of piezoelectric ceramic plate and transducer sound power was analyzed. The envelope of output piezoelectric signal was extracted in twice, a voltage amplitude curve with a sinusoidal distribution was obtained, which could describe the change of acoustic power. Under different drive voltage of the transducer, the maximum peak voltage of envelope curve was found respectively, their squared values were made a linear fit with acoustic power measured by sound power meter, then the proportional coefficient of theoretical relational expression was calibrated. The experimental results presented a good linear correlation, and the relative error between calibrated theoretical sound power and that measured by sound power meter was less than 8.7%, which proved the feasibility of measuring acoustic power of transducer by piezoelectric transient response.