According to an embodiment, an ultrasonic diagnostic apparatus includes an acquirer, first and second generators, and a display controller. The acquirer acquires a 3D ultrasonic image including a heart. The first generator generates a first cross-sectional image of the 3D ultrasonic image including a first axis passing through a second portion in the 3D ultrasonic image and including a third portion. The second portion is a portion by which one of blood inflow into a first portion which is an atrium or a ventricle and blood outflow from the first portion is performed. The third portion is a portion by which another of the blood inflow and the blood outflow is performed. The second generator generates a second cross-sectional image of the 3D ultrasonic image which includes a second axis passing through the third portion and which intersects with the first cross-sectional image. The display controller displays the cross-sectional images.