An ultrasonic diagnostic apparatus capable of obtaining phase information of ultrasonic waves reflected at respective sampling points within an object to be inspected and displaying the phase information in an easy-to-understand-way. The ultrasonic diagnostic apparatus includes: a transmitting and receiving unit for converting reception signals outputted from plural ultrasonic transducers, which have transmitted ultrasonic waves and received ultrasonic echoes, into digital signals reception focus processing means for performing reception focus processing on the digital signals to generate a sound ray signal along a reception direction of ultrasonic waves first calculating means for performing quadrature detection processing on the sound ray signal to generate a complex baseband signal second calculating means for obtaining phase information of the complex baseband signal and image signal generating means for generating an image signal representing phase rotation of the complex baseband signal at plural sampling points along the reception direction of ultrasonic waves based on the phase information of the complex baseband signal.
