The Andrew Jackson Downing Urn, also known as the Downing Urn, is a memorial and public artwork located in the Enid A. Haupt Garden of the Smithsonian Institution on the National Mall in Washington, D.C.[2] The outdoor sculpture of a garden vase−urn commemorates Andrew Jackson Downing (1815–1852), an American landscape designer and horticulturalist, and considered to be one of the founders of American landscape architecture.

[2][3] Shortly before dying at the age of 37, Downing developed a landscape plan for the National Mall that the United States government partially implemented until replacing it with the McMillan Plan of 1902 (see History of the National Mall).

[2] The urn was located and dedicated on the National Mall in September 1856, where it stood near the Smithsonian's National Museum of Natural History until 1965, when it was moved to the east entrance of the Smithsonian Institution Building (the "Castle").

In 1972, the urn was restored, moved to the west entrance of the Castle and rededicated.

In 1987, it was relocated to the Rose Garden at the Castle's east door.