The Monomachus Crown is a set of pieces of engraved Byzantine goldwork, decorated with cloisonné enamel, in the Hungarian National Museum in Budapest, Hungary. It consists of seven gold plates depicting Byzantine Emperor Constantine IX Monomachus, his wife Zoe, her sister Theodora, two dancers and two allegorical figures. Two gold medallions enamelled with saints and a small piece with cut glass in a setting were also found; probably they did not form part of the same object. The group has puzzling aspects that have long made it the subject of scholarly debate; it was probably made in Constantinople in 1042.

The Hungarian National Museum was founded in 1802 and is the national museum for the history, art, and archaeology of Hungary, including areas not within Hungary's modern borders, such as Transylvania; it is separate to the collection of international art in the Hungarian National Gallery. The museum is in Budapest VIII in a Neoclassical building, purpose-built during 1837–47 by the architect Mihály Pollack.