Laparoscopic surgery remains a challenging procedure because visualization of the internal target organ cannot be achieved from the laparoscopic image. We have proposed a laparoscopic surgery support method relying on three-dimensional (3D) images reconstructed using a stereo laparoscope and a 3D ultrasound system. The aim of this study is to develop a visualization system providing depth information about blood vessels within the liver. The shape and depth information of blood vessels are then correctly superimposed on a 2D laparoscopic image on the basis following careful registration. The coordinates of the laparoscope and the ultrasound are registered by aligning the two 3D liver surface shapes obtained by a stereo laparoscope and an ultrasonic diagnostic equipment with a mechanically moved convex probe using multiple image processing techniques. Then, the shape and depth information within the liver are calculated, and colorcoded blood vessel depth information is superimposed on the original 2D laparoscopic image. In a phantom experiment, the registered 3D images were the mean squared error (MSE) of 5.89 ± 3.11 mm. The 2D laparoscopic image was superimposed the color-coded depth of the blood vessels segmented from the 3D ultrasonic data. The calculation of depth information had the MSE of 1.88 ± 1.40 mm.