Provided is an ultrasonic imaging apparatus including: an inputter configured to receive an input of a region of interest, ROI, from a user； a beamformer configured to perform transmission/reception focusing with respect to a virtual source (F1, F2, F3) to be used for a synthetic aperture focusing method； a display； and a main controller configured to determine a position of the virtual source (F1, F2, F3) on the basis of an image quality in the received ROI and control the display to display the determined position of the virtual source (F1, F2, F3).
