Abstract: The principles of electroacoustic reciprocity and self-reciprocity method (SRM) for the plane piston and the spherically focusing transducer are described. A series of definitions with uses of transmitting voltage (current) responses and voltage sensitivity are introduced. The relation of SRM with the radiation force balance (RFB) is expounded. Experiments in frequency range of 1.0~15 MHz show that the two methods are of close accuracy in calibration and output power measurement of ultrasonic transducer. The measurement by SRM is of high signal noise ratio and better stability than by RFB.