This invention is directed to extract the scattering characteristic of a measurement target together when measuring the surface shape in a measurement system, which measures the surface shape of a measurement target, by the pattern projection method. To accomplish this, the measurement system includes an illumination unit which irradiates a measurement target with dot pattern light, a reflected light measurement unit which receives the reflected light at a reflection angle almost equal to a incident angle, and a reflected light extraction unit which extracts the inclination of the surface of the measurement target, based on the shift amount between the light receiving position of the received reflected light and a predetermined reference position, and extracts the luminance value of the reflected light and the dot diameter of the dot pattern light as information about the scattering characteristic.