Provided are an ultrasound system and method that can provide improved storage efficiency of a storage unit by storing only some of a plurality of ultrasound images needed to produce a panoramic image in the storage unit. The ultrasound system includes: an ultrasound data acquisition unit for sequentially acquiring ultrasound data corresponding to a living body a processor for producing a plurality of ultrasound images by using the ultrasound data, setting a region of interest (ROI) on each of the ultrasound images, performing motion estimation between the plurality of ultrasound images to estimate motion of the ROI, and extracting ultrasound images needed for forming a panoramic image from the ultrasound images based on the estimated motion and a storage unit for storing the extracted ultrasound images.