An optical coherence tomography apparatus includes: an acquisition unit configured to split light from a light source into measurement light and reference light, and acquire a tomogram of an eye to be examined based on interfering light obtained by interference between the reference light and return light from the eye a positional relationship changing unit configured to change a positional relationship between the eye and an optical system including an optical path of the measurement light and a control unit configured to control the changing unit based on a difference in slant information of the eye between two tomograms acquired by the acquisition unit.
