Based on the principle of time difference method for flow rate measurement and the principle of thermal resistance for temperature measurement, a kind of calibration device for transducer of ultrasonic heat meter is studied in the paper. The dry calibration device consists of the flow simulation module, temperature simulation module, a microprocessor unit and host computer. The implementation of flow simulation module and temperature difference simulation module is described in detail, as well as the function of the microprocessor. Finally, the comparison result between actual flow calibration data and the dry calibration data from the calibration device in this paper show that the calibration device for transducer of ultrasonic heat meter can effectively implement the function test of ultrasonic heat meter.