An orientation characteristic measurement system includes an irradiation optical system, a detection optical system, a light detector, a rotation mechanism changing an angle (ϕ) between a surface of the sample and an optical axis (L2) of the detection optical system, and a computer, and the computer includes a rotation mechanism control unit controlling the rotation mechanism, a distribution acquisition unit normalizing an angle-dependent distribution of light intensity to acquire an angle-dependent distribution of light intensity, an area specifying unit specifying light intensity in a maximum area on the basis of the angle-dependent distribution of the light intensity, and a parameter calculation unit calculating the orientation parameter (S) on the basis of a linear relationship determined using the film thickness and refractive index of the sample and the light intensity in the maximum area.