Provided is a three-dimensional (3D) ultrasound system (101) for intuitively displaying motion and a method of operating the 3D ultrasound system. The 3D ultrasound system may include a scan unit (103) to generate ultrasonic data of an object through scanning, a coordinate determination unit (105) to determine first coordinates corresponding to a top end of the object, and second coordinates corresponding to a bottom end of the object, from the ultrasonic data, and a display control unit (107) to measure a vector length from the first coordinates to the second coordinates, and to display a color corresponding to the measured vector length by mapping the color to the ultrasonic data.
