He was the first member to join the Straw Hat Pirates, and, to date, is considered the largest threat and most dangerous member in the crew after Luffy. His fame as a master swordsman and his great strength, along with the actions of his captain, sometimes led others to believe he was the true captain of the crew earlier on. He is one of the top three fighters in the crew alongside Luffy and Sanji, and his dream is to become the greatest swordsman in the world. Zoro was regarded as one of "The Eleven Supernovas", the eleven rookie pirates with bounties over Beli100,000,000 to have reached the Red Line before the two year time skip, with a current bounty of Beli120,000,000.
Zoro is a tall, muscular man with lightly tanned skin. He always carries his three swords along with him, bundled up with a green haramaki over his right hip, allowing him to easily draw them with his left hand. Although his right hand is usually seen resting over them, he can also use this hand to pull his swords out before sitting down. He has three identical gold earrings on his left earlobe. Zoro normally keeps a black bandanna tied around his left bicep and ties it around his head when he is fighting seriously against an opponent.
Zoro's body is covered with scars from his many battles, most notably the massive scar stretching from his left shoulder to his right hip that he acquired during his loss against the world's greatest swordsman, Dracule Mihawk, at Baratie. His other visible scars are the scars he inflicted upon his ankles in a desperate attempt to free himself from Mr. 3's Giant Candle Service Set by trying to cut his feet off at Little Garden. After the timeskip, he gained another scar over his left eye, obtained through unknown means.
Zoro's other remarkable feature is his cropped green hair, which Sanji often teases him about by calling him "marimo" (moss-ball, moss-head in the Viz Manga and FUNimation dub) due to its resemblance to one.
Similar to most of his male crewmates, Zoro has the same outfit throughout most of the series. He consistently wears black trousers tucked inside black boots, a plain white shirt with three undone buttons at the collar and his green haramaki. However, only Zoro's shirt varies from time to time in the arcs.
Before the Timeskip
During the Arlong Park Arc, he wore an opened, navy blue shirt decorated with light blue whirlpools. Since Zoro received his scar from Mihawk during the Baratie Arc before the Arlong Park Arc, Zoro wore bandages that were visible underneath his shirt.
During the Drum Island Arc, Zoro was shirtless in the beginning of the arc until he stole a parka from a man in Wapol's army, which is a hooded, forest green parka with a light green sash and white fur on the cuffs, hood, and hem.
During the Alabasta Arc, he wore an orange keffiyeh with a gold chain on his head, a long-sleeved white coat with black lines all over it, and the bottom of his black trousers were torn above his ankles.
During the Skypiea Arc, he wore his usual outfit in the beginning of the arc until he took it off after fighting a skyshark to save Tony Tony Chopper from being eaten. Afterwards, he wore a long, deep blue T-shirt and goggles strapped either on his head or around his neck.
During the Water 7 Arc, he wore his usual outfit until near the end, where he wore an unzipped, bright yellow jacket with a closed pocket flap on each side. He continued wearing this outfit throughout the Enies Lobby Arc.
During the Post-Enies Lobby Arc, he wore a black shirt with the Galley-La Company emblem on it in white.
At the end of the Thriller Bark Arc, he wore an opened, gray shirt.
During the Spa Island Arc, he wore a pale blue v-neck tank top with a pair of army green shorts. He was also barefoot.
During the Sabaody Archipelago Arc, he wore an opened white shirt with red stripes.
During the Little East Blue Arc, he wore a navy blue t-shirt with a red star design tucked into a pair of long red trousers. In addition, he wore straw sandals similar to Luffy's.
During his time at Kuraigana Island, shortly after being sent there by Bartholomew Kuma, he wore an opened, dark blue shirt. Since Zoro was critically injured when he arrived at the island, Perona patched him up, so bandages were all over his body.
After the Timeskip
After the two-year timeskip, Zoro gains a new scar running down his left eye, which is now implied to be critically injured as it is always closed. His neck appears much thicker and more muscular and his hair became a little longer, now slightly slicked back. Zoro now wears a long, open dark-green coat, closed on his waist by a red sash, in which his swords are now tucked, and his black bandanna tied around the left sleeve. He has no shirt underneath, and his green haramaki is visible under the coat. He also appears to have gotten taller, as he seems to be almost as tall as Robin when standing next to her.
During the Punk Hazard Arc, he wore a white furry coat for protection against the cold weather on the frozen side of Punk Hazard, which he took from Brownbeard's Centaur Patrol Unit.
During the Dressrosa Arc, he wore a black suit and a white dress shirt with the top button undone. He also wore black sunglasses and a fake white mustache as a disguise. His sunglasses were destroyed in his clash with Admiral Fujitora. Additionally, he discarded the mustache upon his identity being exposed.