An Important Cultural Property (, j?y? bunkazai)[note 1] is an item officially classified as Tangible Cultural Property by the Agency for Cultural Affairs and judged to be of particular importance to the Japanese people.
To protect Japan's cultural heritage the Law for the Protection of Cultural Properties was created as a "designation system" (?) under which important items are appropriated as Cultural Properties,[note 2] thus imposing restrictions to their alteration, repair and export. Besides the "designation system", there exists a "registration system" (?), which guarantees a lower level of protection and support to Registered Cultural Properties.
Cultural Properties are classified according to their nature. Items designated as Tangible Cultural Properties (as opposed to Intangible Cultural Properties), cultural products of high historical or artistic value such as structures, paintings, sculptures, handicrafts, calligraphic works, ancient books, historic documents, archeological artifacts and other such items, can later, if they satisfy certain criteria, be designated either Important Cultural Properties or National Treasures (), for especially valuable items. The designation can take place at the city (?, city designated Important Cultural Property), prefectural (?, prefecturally designated Important Cultural Property) or national (?, nationally designated Important Cultural Property) level. In this last case the designating agency is often not specified. Varying levels of designation can coexist. For example, Sankei-en, a traditional Japanese-style garden in Naka Ward, Yokohama, is both city and nationally designated as an Important Cultural Properties.