The Old Slave Mart is a building located at 6 Chalmers Street in Charleston, South Carolina that once housed an antebellum-period slave-auction gallery.

Slave auctions were held at the site until approximately 1863; in 1865, the Union Army occupied Charleston and closed Ryan's Mart.

The unique façade of the Old Slave Mart consists of 20-foot (6.1 m) octagonal pillars at each end, with a central elliptical arch comprising the entrance.

Throughout the first half of the 19th century, enslaved people brought into Charleston were sold at public auctions held on the north side of the Exchange and Provost building.

Ryan's Mart originally consisted of a closed lot with three structures — a four-story barracoon or slave jail, a kitchen, and a morgue or "dead house.

[4] In 1938, Miriam B. Wilson purchased the building and established the Old Slave Mart Museum, which initially displayed African and African-American art.

Although Wilson was from Ohio, the Old Slave Mart Museum, under her ownership, embraced local beliefs that slavery had been good for African Americans.

The City of Charleston and the South Carolina African American Heritage Commission restored the Old Slave Mart in the late 1990s.