To set an optimal transmission and reception condition according to a display condition in ultrasonic diagnostic equipment.

A display depth arithmetic part 22 calculates a display depth about the image area of an ultrasonic image. A frequency deciding part 24 decides an optimal center frequency according to the display depth. A display scale factor arithmetic part 26 calculates a display scale factor (magnification ratio) about a display area. A band deciding part 28 decides an optimal band corresponding to the display scale factor. Information of the center frequency and the band decided like this is sent to a transmission and reception part 12, which carries out generation of a transmission signal and processing of a received signal according to the information.