To solve the problems in computer vision based measurement for smooth and continuous specular surface, an imaging simulation measurement method is proposed. The geometrical optics principle for specular surface is studied. A setup which consists of a camera and a LCD display is used to measure the specular objects. A parametric surface is used to simulate the specular surface whose optics property is similar to a smooth curved surface. A simulation incident light ray which is determined by the original point of the camera and the pixel on the image plane reaches the parametric surface, then is reflected by the law of reflection. The 3D points of the specular surface are obtained when the errors between the intersections of simulation reflect rays and the real points of the LCD display are minimized. The experiment results show that this method is effective and obtains high accuracy.