Seodaemun Prison History Hall is a museum and former prison in Seodaemun-gu, Seoul, South Korea. It was constructed beginning in 1907. The prison was opened on October 21, 1908, under the name Gyeongseong Gamok. Its name was changed to Seodaemun Prison in 1923.
The prison was used during the Colonial period to house anti-colonial activists, and could accommodate around 500 people. After the colonial era ended in 1945, the prison was used by the South Korean government until 1987, when it was replaced by a facility in Uiwang City, Gyeonggi Province. In 1992, the site was dedicated as the Seodaemun Prison History Hall, part of Independence Park. Seven of the prison complex's original fifteen buildings are preserved as historical monuments.