Based on the ultrasonic tomographic data measured by exerting the pressure to the tissue of a body of the subject 1, the elastic data such as the distortion or the elastic modulus of the tissue at the plural measurement points in the tomographic site of the subject body are obtained. Based on the obtained elastic data, the elastic image in the tomographic site is generated to be displayed. The distribution of the elastic data such as the distortion and the elastic modulus in the interest region ROI set on the elastic image is displayed as the histogram. The new quantitative information which reflects the tissue property is supplied in addition to the information which relates to the elasticity of the tissue graded with the hue or brightness for assisting in the tissue identification.
