The Imperial Crown of the Holy Roman Empire, a hoop crown with a characteristic octagonal shape, was the coronation crown of the Holy Roman Emperor, probably from the late 10th century until the dissolution of the Holy Roman Empire in 1806. The crown was used in the coronation of the King of the Romans, the title assumed by the Emperor-elect immediately after his election. It is now kept in the Imperial Treasury at the Hofburg in Vienna, Austria.

A hoop crown, arched crown, or closed crown, is a crown consisting of a "band around the temples and one or two bands over the head". First used by the Carolingian dynasty, hoop crowns became increasingly popular among royal dynasties in the Late Middle Ages, and the dominant type of crown in the Modern Era.