Abstract: Surgical operation supporting apparatus and method is disclosed in which based on a high-definition tomographic images of an operation site produced before surgery, a three-dimensional model of the operation site is generated, and a surface of the operation site is optically measured during the surgical operation, and further, first position information that represents a three-dimensional position of each of points on the surface is acquired. An unexposed portion of the operation site is measured with ultrasonic waves during the surgical operation, and second position information that represents a three-dimensional position of each of points in the unexposed portion is acquired. Based on the first position information and the second position information, displacement and distortion at a portion whose three-dimensional position is not known in the three-dimensional model is estimated to obtain an estimated result.