An ultrasound imaging apparatus comprising: an ultrasound probe configured to generate a three-dimensional imaging signal of an object by transmitting an ultrasound beam, wherein the ultrasound probe comprises a detecting unit configured to detect a relative position of the ultrasound probe relative to a reference position and a relative location of the ultrasound probe relative to a reference location; a display unit configured to display a diagnostic image in a first section based on the imaging signal, and display an image indicator indicating a target part of the object in a second section; and a controlling unit configured to synchronize the diagnostic image with a selected reference image corresponding to the diagnostic image and to set the position and location of the ultrasound probe at the time of synchronization as the reference position and location of the ultrasound probe, wherein the reference image comprises a cross-sectional image of a three dimensional volume image; wherein the image indicator comprises a target organ marker which is configured to display the target part as a three dimensional volume image identical to the three dimensional volume image of the reference image and to display a beam direction marker which indicates the direction of the ultrasound probe beam in three dimension; and wherein the display unit is configured to display a plurality of reference images similar to the diagnostic image in a third section, the ultrasound imaging apparatus further comprises an input unit configured to receive a selection of one image as the selected reference image among the plurality of reference images from a user, and the controlling unit is configured to move the image indicator according to the relative position and the relative location. an ultrasound probe configured to generate a three-dimensional imaging signal of an object by transmitting an ultrasound beam, wherein the ultrasound probe comprises a detecting unit configured to detect a relative position of the ultrasound probe relative to a reference position and a relative location of the ultrasound probe relative to a reference location; a display unit configured to display a diagnostic image in a first section based on the imaging signal, and display an image indicator indicating a target part of the object in a second section; and a controlling unit configured to synchronize the diagnostic image with a selected reference image corresponding to the diagnostic image and to set the position and location of the ultrasound probe at the time of synchronization as the reference position and location of the ultrasound probe, wherein the reference image comprises a cross-sectional image of a three dimensional volume image; wherein the image indicator comprises a target organ marker which is configured to display the target part as a three dimensional volume image identical to the three dimensional volume image of the reference image and to display a beam direction marker which indicates the direction of the ultrasound probe beam in three dimension; and wherein the display unit is configured to display a plurality of reference images similar to the diagnostic image in a third section, the ultrasound imaging apparatus further comprises an input unit configured to receive a selection of one image as the selected reference image among the plurality of reference images from a user, and the controlling unit is configured to move the image indicator according to the relative position and the relative location.