PURPOSE: To provide an ultrasonic diagnostic device capable of harmonizing two contrary diagnostic capacities that are space resolution and time resolution.

CONSTITUTION: A focus switch 5 has four focus selector switches with the focus depth respectively set so as to be able to set a first stage focus, a second stage focus, a third stage focus and a fourth stage focus by various kinds of combinations. When one or more focus selector switches of the focus switch 5 are pressed, delay data for setting the corresponding focus depth is computed or read from a memory in a controller 4. The delay data is supplied to a transmission control circuit 2 or a receiving control circuit 3 where adjustment is added thereto, and control for performing B-mode scanning with focus is executed.