A non-contact ultrasonic tonometer for measuring an intraocular pressure of an examinee's eye in non-contact manner by use of an ultrasonic wave, comprises: an ultrasonic transducer including a transmitter which emits an ultrasonic transmission pulse wave to the eye and a receiver which detects an ultrasonic reflection pulse wave from the eye, the transducer being arranged to be placed in a position apart from the eye and to transmit and receive the pulse wave with respect to the eye through the medium of air; and a calculation part being arranged to obtain a peak amplitude level of the reflection pulse wave based on an output signal from the ultrasonic transducer and measure the intraocular pressure based on the obtained peak amplitude level.