Embodiments of the present application relate to an image index generation method, system, a device, and a computer program product. An image index generation method is provided. The method includes selecting an image included in an image library for which an image index is to be generated, determining at least one target region included in the image, extracting visual features from the determined at least one target region, determining a similarity value of the selected image and image included in the image library based on the extracted visual features, determining image categories to which the images belong to based on the determined similarity values among the images, and assigning category identifiers to the images in accordance with an identifier assignment method, the identifier assignment method assigns the same category identifiers to images belonging to the same image category, and different category identifiers to images belonging to different image categories.