Provided is a method of generating an ultrasound image corresponding to a cross-section of interest, which is performed by an ultrasound imaging apparatus. Exemplary embodiments include a method of generating an ultrasound image corresponding to a cross-section of interest of an object by storing ultrasound echo signals respectively corresponding to a plurality of frames that constitute a three-dimensional (3D) ultrasound image of the object, performing beamforming on a focal point on the cross-section of interest of the object, and generating beam focused data for the focal point.
