An eye movement measuring device for detecting an eyeball-state/movement including: an eyeball photographing device configured to take a photograph of an eyeball; and an eye movement detecting unit configured to detect eye movement based on eyeball image as a photograph taken with the eyeball photographing device, the eyeball photographing device including an eyeball illuminating unit configured to illuminate an eyeball of a subject including a driver with illumination light, an eyeball image imaging unit configured to obtain eyeball image as a result of imaging the illuminated eyeball, and an arranging unit configured such that, when the eyeball photographing device is worn by the subject, the eyeball illuminating unit is arranged in a position where the eyeball can be irradiated with the illumination light, and the eyeball image imaging unit is arranged in a position where the eyeball image can be obtained as a result of the imaging.