A gaze detection apparatus comprising: a light source (103a, 103b) configured to irradiate right and left eyeballs of a subject with detection light; a camera (102a, 102b) configured to capture images of the right and left eyeballs irradiated by the detection light; a position detection unit configured to detect positions of pupil centers indicating centers of pupils of the right and left respective eyeballs and positions of corneal reflection centers indicating centers of corneal reflexes of the right and left respective eyeballs from the image of the left and right eyeballs irradiated with the detection light; a curvature radius calculation unit configured to calculate corneal curvature radii of the right and left respective eyeballs from a position of the light source (103a, 103b) and the positions of the corneal reflection centers; a gaze detection unit configured to detect gaze directions of the right and left respective eyeballs from the positions of the pupil centers and the corneal curvature radii; a display unit; a viewpoint detection unit configured to detect viewpoints of the right and left respective eyeballs on the display unit, from the gaze directions detected in the gaze detection unit; an output control unit configured to display the viewpoints of the right and left respective eyeballs on the display unit; and a determination unit configured to determine whether both the right and left eyeballs move along a target direction on the basis of a first movement locus of the viewpoints of the left eyeball, a second movement locus of the viewpoints of the right eyeball, and an area defined by the first movement locus and the second movement locus. a light source (103a, 103b) configured to irradiate right and left eyeballs of a subject with detection light; a camera (102a, 102b) configured to capture images of the right and left eyeballs irradiated by the detection light; a position detection unit configured to detect positions of pupil centers indicating centers of pupils of the right and left respective eyeballs and positions of corneal reflection centers indicating centers of corneal reflexes of the right and left respective eyeballs from the image of the left and right eyeballs irradiated with the detection light; a curvature radius calculation unit configured to calculate corneal curvature radii of the right and left respective eyeballs from a position of the light source (103a, 103b) and the positions of the corneal reflection centers; a gaze detection unit configured to detect gaze directions of the right and left respective eyeballs from the positions of the pupil centers and the corneal curvature radii; a display unit; a viewpoint detection unit configured to detect viewpoints of the right and left respective eyeballs on the display unit, from the gaze directions detected in the gaze detection unit; an output control unit configured to display the viewpoints of the right and left respective eyeballs on the display unit; and a determination unit configured to determine whether both the right and left eyeballs move along a target direction on the basis of a first movement locus of the viewpoints of the left eyeball, a second movement locus of the viewpoints of the right eyeball, and an area defined by the first movement locus and the second movement locus.