An image processing method comprising acquiring a first fundus image obtained by photographing a fundus using first light having a first wavelength, and a second fundus image obtained by photographing the fundus using second light having a second wavelength that is shorter than the first wavelength; specifying, in the first fundus image, respective positions of retinal blood vessels appearing in the second fundus image; and generating a choroidal blood vessel image by processing the positions identified in the first fundus image.