To provide an ophthalmic ultrasonic diagnostic apparatus capable of obtaining measurement result with high reliability without lengthy measurement. The apparatus which measures constituent parts of an eye through A-mode includes an ultrasonic probe for A-mode measurement including a transducer emitting an ultrasonic wave into the eye and receiving reflected echoes from tissues of the parts, calculation means for judging whether signals of the echoes are appropriate and calculating measurement values of the parts based on the signals, a memory storing the calculated values, grouping means for setting grouping ranges having predetermined ranges of permissible dispersion with reference to the measurement values and determining that either the grouping range previously set or the grouping range newly set based on the obtained measurement value remains, and central value calculating means counting the numbers of the measurement values falling within the grouping ranges and calculating a central value based on the measurement values.