A method for monitoring an image of an examinee's eye includes: obtaining first image data including a first examinee's eye image captured by a first ophthalmologic photographing apparatus, and additional information including type information on the first examinee's eye image; obtaining second image data including a second examinee's eye image captured by a second ophthalmologic photographing apparatus different from the first ophthalmologic photographing apparatus, and additional information including type information on the second examinee's eye image; recognizing the first examinee's eye image and the second examinee's eye image as the same type of images, based on the additional information; and correcting a difference between the first examinee's eye image and the second examinee's eye image.