An object of the present invention is to more accurately detect a gaze vector along a subject's gaze direction. According to one embodiment, a gaze vector detection device according to an embodiment includes a plurality of IR illumination devices that respectively irradiate examination light to an eyeball of a subject, an imaging device that picks up a reflection image of the examination light by the eyeball, An optical axis vector calculation unit that calculates an optical axis vector based on the position of the reflected image when viewing an object, the spatial coordinates of the visible object, and the spatial coordinates of the corneal curvature center assuming the cornea of the subject . [Selected figure] Figure 2【課題】被験者の視線方向に沿った視線ベクトルをより正確に検出する。【解決手段】実施形態の視線ベクトル検出装置は、検査光を被験者の眼球にそれぞれ照射する複数のＩＲ照明装置と、検査光の前記眼球による反射像を撮像する撮像装置と、被験者が所定の視認対象物を視認しているときの前記反射像の位置、視認対象物の空間座標及び被験者の角膜を想定した角膜曲率中心の空間座標に基づいて、光軸ベクトルを算出する光軸ベクトル算出部と、を備える。【選択図】 図２
