1. A method of analyzing elastography of tissue using ultrasound waves, the method comprising: irradiating a region of interest (ROI) in a subject with ultrasound waves using an ultrasound probe having a two-dimensional (2D) transducer array, wherein a shear wave is induced in the ROI by the irradiating; acquiring three-dimensional (3D) ultrasound images with respect to the ROI using echo ultrasound waves of the ultrasound waves, wherein the echo ultrasound waves have been received by the ultrasound probe; measuring a displacement of the shear wave in the ROI based on the 3D ultrasound images received by the ultrasound probe; and analyzing information about elastography of tissue in the ROI using the measured displacement of the shear wave.