Metlika Castle is a 15th-century castle located above the old part of the town of Metlika in southeastern Slovenia, very near the Croatian border.
The castle is first mentioned in written sources in 1456. During the period of Ottoman incursions in the 15th and 16th century, it was owned by the Counts of Alap, and had a key role in defense against the Turks. Later, the castle was owned by the house of Frankopan, and later yet by the chapterhouse of the bishopric of Zagreb.
During the 18th century, the castle was twice damaged by fire (in 1705 and 1790); after repairs it was in 1792 bought by Jožef Savinšek. It survived World War II intact and was afterward nationalized and converted into the headquarters of the Museum of White Carniola (Slovene: Belokranjski muzej), established in 1951, and became home to some of its permanent collections.