1. An ultrasonic diagnostic apparatus comprising: a displacement measuring section for transmitting ultrasonic waves from a probe to an object to be examined, receiving the reflected echo signals corresponding to the transmitted ultrasonic waves, and measuring displacement of organism tissues of the object based on the reflected echo signals; a tomographic image constructing section for constructing B-mode tomographic image from the reflected echo signals; an elastic image constructing section for constructing elastic images by obtaining distortion or elastic modulus from said displacement; a display section for displaying a superposed translucence color image of the elastic image, indicating distribution of hardness of the tissues on the B-mode tomographic image; and a scoring section configured to classify the elastic image into score corresponding to the distorted state or elastic state, the score being based on whether area of a hard portion of the superposed translucence color image of the elastic image reaches circumference of the low echo region of the B-mode tomographic image, within low echo region of the B-mode tomographic image.