The 320 South Boston Building is a 22-story high-rise building located in downtown Tulsa, Oklahoma. It was originally constructed at the corner of Third Street and Boston Avenue as a ten-story headquarters building for the Exchange National Bank of Tulsa, Oklahoma in 1917, and expanded to its present dimensions in 1929. The addition brought the building's height to 400 feet (122 m), making it the tallest building in Oklahoma. It lost this distinction in 1931, but remained the tallest building in Tulsa until Fourth National Bank was completed in 1967. It is now included in the Oil Capital Historic District.

Downtown Tulsa is an area of approximately 1.4 square miles (3.6 km2) surrounded by an inner-dispersal loop created by Interstate 244, US 64 and US 75. The area serves as Tulsa's financial and business district; it is the focus of a large initiative to draw tourism, which includes plans to capitalize on the area's historic architecture. Much of Tulsa's convention space is located in downtown, such as the Tulsa Performing Arts Center and the Tulsa Convention Center, as well as the BOK Center. Prominent downtown sub-districts include the Blue Dome District, the Tulsa Arts District, and the Greenwood Historical District, which includes the site of ONEOK Field, a baseball stadium for the Tulsa Drillers opened in 2010.