According to one embodiment, an ultrasound diagnosis apparatus includes a change amount calculating unit, an estimating unit and a control unit. The change amount calculating unit is configured to calculate amount of change of a pattern of each of a plurality of local regions among a plurality of ultrasound images generated along time series based on a reflected wave of an ultrasound wave transmitted by an ultrasound probe. The estimating unit is configured to estimate a position of a rotation axis of a scanning cross-section in each ultrasound image based on the amount of change of the pattern of each of the plurality of local regions calculated by the change amount calculating unit. The control unit is configured to superimpose the rotation axis estimated by the estimating unit on each ultrasound image and displays the same on a monitor.