The principle of simple ultrasonic hydrophone is briefly introduced.The structural design and fabrication method are discussed in detail as well.The experiment results show that the ultrasonic hydrophone has the characteristic of high sensitivity

simple and practical.It has strong anti-jamming ability while the cost is merely 3 % of hydrophone.The sensitivity of simple subaqueous ultrasonic transducer is 95 % of hydrophone in 40 kHz.The working frequency range is 10

1

00 kHz.It is calibrated by the CS—3 hydrophone.Ultrasonic hydrophone could be widely used as subaqueous ultrasonic pressure sensor in simple measurement.