To reduce the load of an operator when scanning ultrasound in three dimensions.

In an ultrasonograph of one embodiment, a display controller 18a controls so as to display images (an MPR image and a volume image of perpendicular three cross-sections) generated from ultrasonic volume data in a monitor 2. A moving vector calculator 18b calculates a moving vector of three dimensional area of interest between the ultrasonic volume data generated in time series. Further, a moving amount calculator 18c calculates the moving amount of the three dimensional area of interest in the ultrasonic volume data newly generated based on the moving vector calculated by the moving vector calculator 18b. Furthermore, a controller 18d adjusts such that the positions of the areas of interest in the volume image displayed in a monitor 2 are substantially the same based on the moving amount calculated by the moving amount calculator 18c.