Darcelle XV Plaza, Urban park in downtown Portland, United States.

Darcelle XV Plaza is a small square at Southwest Park Avenue and Southwest Harvey Milk Street in downtown Portland, Oregon. It was built as O'Bryant Square with a parking garage beneath it and is being redeveloped to open in 2025 with a stage, a dog park, a large shade sail over the centre, public art and a wall of fame for Portland's LGBTQ community.

The site once held a quarter-block building and surface parking before Mr. and Mrs. William E. Roberts donated it to the city in 1971. The park and its underground garage, costing $1.25 million, opened in 1973 as O'Bryant Square, named for Portland's first mayor Hugh D. O'Bryant. It closed in March 2018 over structural problems in the garage, and in July 2023 was renamed Darcelle XV Plaza after the drag performer (1930–2023).

The plaza is named for Darcelle XV, the drag persona of Walter Cole (1930–2023), who ran the Darcelle XV Showplace and was certified by Guinness World Records in 2016 as the oldest performing drag queen. Plans for the redeveloped plaza include public art and a wall of fame commemorating Portland's LGBTQ community.

The plaza sits at Southwest Park Avenue and Southwest Harvey Milk Street, closed since March 2018 for structural problems in the underground parking garage and under redevelopment, with opening set for 2025. The design adds a stage, a fenced dog area and a large shade sail over the center.

This is Portland's first enclosed city park, an uncommon design choice for a public space in the city. The fencing was chosen to create a protected dog area and a defined green space within the downtown core.