An ultrasound diagnostic apparatus includes an alignment unit, a detector and a generator. The alignment unit performs alignment between three-dimensional ultrasound volume data and three-dimensional different-type medical image volume data of a type other than the three-dimensional ultrasound volume data. The detector specifies the position of a luminal area on the different-type medical image volume data and detects the specified position of the luminal area on the ultrasound volume data. The generator generates, as display image data to be displayed on a given display unit, projection image data obtained by projecting the ultrasound volume data from a viewpoint that is set in the luminal area on the basis of the position of the luminal area that is detected by the detector.
