Powder Magazine, Military history museum in Charleston, United States.

The Powder Magazine is a museum in Charleston dedicated to military history and housed in a sturdy brick building. The structure has thick walls, gables, and a red tile roof in a square form on Cumberland Street.

Construction was authorized by the Province of Carolina in 1703, during Queen Anne's War, as part of a series of fortifications, but the building was not completed until 1713. It stored gunpowder through the American Revolutionary War, then served other uses, among them a wine cellar for Gabriel Manigault. The National Society of the Colonial Dames of America acquired it in 1902 and has run it as a museum since.

Since 1902 the building has been owned by the local chapter of the National Society of the Colonial Dames of America, which runs it as a museum of historic artifacts and displays on the Colonial and Revolutionary periods. The name Powder Magazine comes from its original role as the colony's gunpowder store.

The building stands on the south side of Cumberland Street between Church and Meeting Streets, in Charleston's historic centre. It closed in February 2025 for repairs while the Colonial Dames reviewed options for its future; in May 2026 the City of Charleston agreed to run the museum with longer hours and events, so check current opening arrangements before travelling.

The walls are about 32 inches thick and taper toward the top to control and disperse explosive forces. This special construction was necessary to protect the ammunition stored inside.