A diagnostic ultrasound system includes an ultrasound transmitting and receiving system for transmitting and receiving ultrasonic waves to and from a object to be examined 10, an elasticity image capturing system for capturing an elasticity image related to body tissue of the object to be examined on the basis of a signal output from the ultrasound transmitting and receiving system, and a controlling and displaying system for capturing the elasticity image. The elasticity image capturing system obtains compression data related to the compression state of the object to be examined 10, determines the compression state of the body tissue on the basis of the compression data, and includes a compression direction and range evaluation unit 115 as a compression state evaluating means for reflecting the determination result to the elasticity image. In this way, more accurate diagnosis by objectively and quantitatively grasping the compression state of the body tissue is possible.