A Windsor uniform is a black and gold uniform worn on ceremonial occasions mostly by British colonial officials.

The uniform was created by King George III in 1777 for members of his royal court. It consists of a black button-down high-collar jacket with leafy golden embroidery on the chest, cuffs and long tails; black breeches with golden piping at each side; and a cocked hat with white ostrich plumes.

The uniform was worn mainly by governors and other colonial officials within the British Empire. In the 20th century it became popular among the Governors General, Lieutenant governors, ambassadors, and even Prime Ministers of Commonwealth Realm countries. The uniform was also copied by numerous other (mostly European) nations, and became the standard diplomatic uniform until as late as the 1970s. Today the uniform is rarely seen.