Full dress uniform, also known as a ceremonial dress uniform or parade dress uniform, is the most formal type of uniforms used by military, police, fire and other public uniformed services for official parades, ceremonies, and receptions, including private ones such as marriages and funerals. Full dress uniforms typically include full-size orders and medals insignia. Styles tend to trace back to uniforms used during the 19th century, although the 20th century saw the adoption of mess dress-styled full-dress uniforms. Designs may depend on regiment or service branch (e.g. army, navy, air force, marines). In Western dress codes, full dress uniform is a permitted supplementary alternative equivalent to the civilian white tie for evening wear or morning dress for day wear – sometimes collectively called full dress – although military uniforms are the same for day and evening wear. As such, full dress uniform is the most formal uniform, followed by the mess dress uniform.

Although full dress uniforms are often brightly coloured and ornamented with gold epaulettes, braids, lanyards, lampasses, etc., most originated as practical uniforms that, with the adoption of even more practical uniforms, were relegated to ceremonial functions. Before World War I, most armed forces of the world retained uniforms of this type that were usually more colourful and elaborate than the ordinary duty (known as undress), or the active service dress uniform.

While full dress uniform is predominantly worn at occasions by commissioned officers and non-commissioned officers, it may also be worn as an optional uniform by some senior enlisted personnel. It is also sometimes worn by members of royal courts, orders of chivalry or certain civilian uniformed services, although some of these may border to court uniforms.