An image processing apparatus includes a detection unit configured to detect layers on the retina based on tomographic images of the retina, an acquisition unit configured to acquire a region having a larger curvature of the boundary surface between the retina and the corpus vitreum than a threshold value, and a determination unit configured to determine an optic disc of the retina based on the optical disc including a region where a specific layer is not detected by the detection unit and the region acquired by the acquisition unit.