A driving circuit for a piezoelectrically actuated pump includes a boost converter, a control circuit and a voltage switch circuit. The boost converter outputs a constant voltage. The control circuit includes a voltage-division circuit, a comparator and a frequency adjustment circuit. The constant voltage is divided by the voltage-division circuit into a first voltage and a second voltage. The comparator compares first voltage with second voltage so as to output a positive voltage or a negative voltage. The voltage switch circuit receives and feedbacks positive voltage or negative voltage to the piezoelectric actuator load. The control circuit and the voltage switch circuit form a resonant circuit to control the piezoelectric actuator load according to the variety of minor voltage outputted form the piezoelectric actuator load. The frequency adjustment circuit detects and adjusts the variety of the minor voltage automatically so as to adjust operating frequency of the piezoelectric actuator load.