The number of signal lines connecting an ultrasonic probe and an ultrasonic diagnostic apparatus main body is reduced or wireless communication is realized by reducing a volume of data of reception signals outputted from plural ultrasonic transducers. The ultrasonic probe includes: plural ultrasonic transducers for transmitting ultrasonic waves according to drive signals and receiving ultrasonic echoes to output reception signals； signal processing units for performing orthogonal detection processing or orthogonal sampling processing on the reception signals to generate two signals representing a complex baseband signal； sampling units for sampling the two signals to generate parallel sample data； a serializing unit for converting the parallel sample data into serial sample data； and a transmitting unit for transmitting the serial sample data.
