An ultrasonic driving device with multi-frequency scanning that includes a signal generating module, an output module, and an ultrasonic transducer module. The signal generating module provides a first drive signal, the frequency of which varies within a specified range. The output module is connected electrically to the signal generating module for receiving the first drive signal therefrom, and for adjusting amplitude of the first drive signal to result in a second drive signal. The ultrasonic transducer module is connected electrically to the output module for receiving the second drive signal therefrom, and for producing ultrasounds, the frequency of which corresponds to that of the second drive signal.