Provided are an ultrasound system and a method of providing a reference image corresponding to an ultrasound image of a target. The ultrasound system includes: a storage unit configured to store a plurality of images corresponding to respective targets; and a processor configured to generate an ultrasound image which depicts the target included in a subject by using ultrasound data acquired from the subject, extract at least one reference image corresponding to the ultrasound image from among the plurality of images, and control a display of the reference image extracted.