An optimal high-speed multi-resolution retrieval method includes the steps of sorting all data contained in a database into a desired number of clusters each composed of data having similar features, deriving the lower bound of the distance between each cluster and a query, removing clusters having no possibility to be determined as best matches, searching, for best matches, data of clusters having the possibility to be determined as best matches, and inducing an inequality property based on a multi-resolution data structure for reducing unnecessary feature matching computation involved in a search procedure to reduce a large quantity of calculation.