Before Death
Before his death, Brook was a tall, skinny man who had a rather distinctive face. He had a slight goatee on his chin and some side burns. He typically wore shades never revealing his eyes. On his forehead was a scar that slightly resembles a diagonal omega sign (Ω). This scar was retained in his skeletal state as a distinctive crack across his skull. Brook's facial appearance, accompanied with his style of clothing, resembles a type of appearance and style that is commonly associated with various music artists such as Ozzy Osbourne, Jimi Hendrix, Slash, and other musical celebrities with similar features.
Before the Timeskip
Brook is an extremely tall skeleton dressed in formal attire complete with top hat and cane. At 8' 8.5" in height, he is the tallest member of the Straw Hat crew. Despite having no skin, he still has an afro which he says is because his hair has very strong roots. Brook's style was that of a gentleman consisting of a coat, top hat, trousers and afro, which were black, while the inner linings of his coat were yellow-orange. The cravat that was tied in between his coat and around his neck was blue. The outer covering of Brook's cane sword which he carries was purple. Also, due to his many years of seclusion his clothes were somewhat tattered.
After the Timeskip
He has now changed to more colorful and high-end clothes, as though to represent a rock star. He has heart-shaped sunglasses, a yellow feather boa, a top hat with a giant crown on the brim and orange red trousers with a floral design. He also grew to 9'1", and remains as the tallest Straw Hat member.
During the Punk Hazard Arc, he wore a flashy striped coat, after taking it from a member of Brownbeard's Centaur Patrol Unit.