In an ultrasonic diagnostic apparatus for performing serial transfer between an ultrasonic probe and an apparatus main body, stable image formation can be performed even when transfer quality is poor while realizing downsizing of the ultrasonic probe. The apparatus includes: (i) an ultrasonic probe including a reception signal processing unit for generating parallel sample data based on reception signals outputted from plural ultrasonic transducers, a parallel/serial conversion unit for converting the parallel sample data into serial sample data, and a communication unit for transmitting the sample data； and (ii) an ultrasonic diagnostic apparatus main body including a storage unit for storing the sample data of at least one frame transmitted from the ultrasonic probe, and an image forming unit for generating an image signal by performing reception focusing processing on the sample data with respect to every one frame read out from the storage unit.
