An ultrasonic wave diagnostic apparatus according to an embodiment includes processing circuitry. The processing circuitry acquires a plurality of pieces of volume data obtained through image capturing of a region including the cardiac ventricle of a subject for a predetermined duration. The processing circuitry estimates motion of tissue of the cardiac ventricle by using the pieces of volume data. The processing circuitry calculates, based on a result of the estimation, cardiac ventricle information indicating at least one of wall motion information and volume information related to the cardiac ventricle. The processing circuitry calculates, based on a result of the estimation, annulus information related to the size or shape of an annulus position of a valve related to inflow or outflow of blood current at the cardiac ventricle. The processing circuitry outputs the cardiac ventricle information and the annulus information.