The Ohio Burgee is the official flag of the U.S. state of Ohio. It is a triangular swallowtail flag. Its red, white, and blue elements symbolize the state's natural features and order of admission into the Union. A prominent disc in the flag's triangular canton is suggestive of the state's name. The flag was adopted in 1902.

A flag is a piece of fabric with a distinctive design and colours. It is used as a symbol, a signalling device, or for decoration. The term flag is also used to refer to the graphic design employed, and flags have evolved into a general tool for rudimentary signalling and identification, especially in environments where communication is challenging. Many flags fall into groups of similar designs called flag families. The study of flags is known as "vexillology" from the Latin vexillum, meaning "flag" or "banner".