In this study, we developed a method of real-time tracking of tissue contour with a relatively low exposure by use of Computed Tomography (CT) and Ultrasonic (US) Image. Even if it is difficult to extract tissue contour in US image, the proposed method made real-time tracking of tissue contour possible by complementary usage the contour information in CT image and the remaining motion information in US image. Specifically, the identified target contour information in CT image was traced onto the corresponding position in US image. The motion vector of the target tissue contours was estimated by speckle tracking of its surroundings. The target tissue contours in the CT image was animated by using the motion vector. The results of the evaluation test shown the possibility of real-time tissues tracking by the proposed method.