Seoul Plaza is a central plaza located in front of Seoul City Hall at Taepyeongno, Jung-gu in Seoul, South Korea. It was reopened on 1 May 2004, by Seoul Metropolitan Government, with the purpose of providing the public an open space. It is part of the City's plans for environmentally friendly renovation projects such as the Cheonggye Stream and Gwanghwamun Plaza.

The site was originally a traffic square with a 40-year-old fountain that was demolished and the nearby space was renovated. Seoul Plaza is elliptical in shape, covering 3,995 pyeong (13,207 m²) in total and 1,904 pyeong (6,294 m²) for grass area. An underground water tank was installed along with 48 lighting around the grass square. The underground tank stores rain water for use in the sprinklers on the lawn.