An ultrasonic diagnostic apparatus according to an embodiment comprises a data acquisition unit configured to execute ultrasonic scanning for a tissue region throughout a predetermined period and acquire a plurality of image data respectively corresponding to phases in the predetermined period a positional information acquisition unit configured to acquire positional information of a region of interest in the tissue region at least one phase in the period by executing tracking processing using at least part of the plurality of image data a shape information calculation unit configured to calculate shape information corresponding to the region of interest at least one phase in the period by using positional information of the region of interest at the at least one phase and an output unit configured to output the shape information at the at least one phase.
