An image processing apparatus determines categories for classifying image data based on shooting information of the image data, generates an update information file for each category, and uploads the update information file along with the image data to an image managing server. A client terminal registers, in advance, the address of a desired update information file, and periodically checks the update information file in the image managing server. If the update information file indicates that new image data has been added to the image managing server, the image data is downloaded in accordance with the file path described in the update information file.