In an ultrasonic diagnostic apparatus (10), a set of transmitting conditions ML1 optimal for existential diagnosis and two transmitting conditions ML2 and ML3 optimal for qualitative diagnosis are defined for the contrast echo method and selected appropriately according to a sequence of diagnosis for the purpose of gathering and processing ultrasonic images. The transmitting conditions can be switched automatically, from one to the other, or in accordance with a command issued by the operator due to the program registered in advance. A flash transmission is conducted on the transmitting conditions MLh between an existential diagnosis and a qualitative diagnosis. This enables the user to observe the new in-flow of contrast medium into the region being observed.