The Bleach storyline series features a large number of characters created by Tite Kubo. The series takes place in a fictional universe in which the characters are divided into various factions and fictional races with distinct themes. All these races are human beings, that in the moment they died, they were able or not to rest in peace. Souls who manage to rest go to a place called Soul Society where they live for a long time until resurrecting in a new body or they instead can become Soul Reapers, who take care of souls.

The series opens telling how a teenager called Ichigo Kurosaki is given Soul Reapers power by Rukia Kuchiki. As he assumes the duties of a Soul Reaper, Ichigo has to fight against giant creatures called hollow which are really dead people who are not able to rest in peace. As he faces several hollows, some of his friends awake their own powers due to being close to him and start helping him. However, Soul Society, a type of military of Soul Reapers arrests Rukia for giving her powers to Ichigo and prepare to execute her. Unwilling to let her die, Ichigo and his friends go to rescue her to Soul Society, causing them to face several Soul Reapers. As the storyline continue, a former Soul Reaper called Sōsuke Aizen gathers a large number of hollows called arrancar, who obtained Reaper powers and prepares to attack Soul Society.

Ichigo Kurosaki (Kurosaki Ichigo) is the primary protagonist of Bleach, orange-haired high school junior Ichigo is forced to become a substitute Soul Reaper after unintentionally absorbing most of Rukia's powers. His cynical nature at first makes him ill-disposed towards the duty, but with the passage of time he comes to accept and welcome the strength his Soul Reaper powers give him, as it allows him to protect those close to him. In the Japanese series, he is voiced by Masakazu Morita while in the English adaptation he is voiced by Johnny Yong Bosch.

Rukia Kuchiki (Kuchiki Rukia) is a sarcastic Soul Reaper who is assigned hollow extermination duties in Ichigo's hometown. Though her physical appearance is that of a teenage girl, in reality she is around 150 years old. At the opening of the story, Rukia is forced to transfer her powers to Ichigo and assume a temporary lifestyle as a regular human. She registers at the local high school and takes up residence in Ichigo's closet, while teaching him how to be a substitute Soul Reaper in her place. She is voiced by Fumiko Orikasa in Japanese and by Michelle Ruff in English.

Orihime Inoue (Inoue Orihime) is a long-time classmate of Ichigo, closely linked to him by mutual friend Tatsuki Arisawa. She is effectively an orphan, as when she was 3, her older brother Sora left their abusive parents' home with Orihime and raised her on his own, later on, when Orihime was in middle school he died in a car accident. Though initially devoid of spiritual powers, she develops spiritual awareness early in the plot and later obtains one of the strongest powers in the Bleach universe, a god-like ability to reject fate. She is voiced by Yuki Matsuoka in the Japanese series and by Stephanie Sheh in the English dub.

Uryū Ishida (Ishida Uryū, rendered as "Uryū" in the VIZ Media manga and "Uryu" in the VIZ Media anime and Bleach: The 3rd Phantom) is a Quincy, descendant of a line of priest-like hollow-hunting archers who were historical enemies of the Soul Reapers. He bears a deep grudge against all Soul Reapers, including Ichigo, and is an early antagonist in the series. He comes to view Ichigo differently over time, however, eventually becoming a valuable ally and friendly rival. He is voiced by Noriaki Sugiyama in Japanese and Derek Stephen Prince in English.

Yasutora Sado (Sado Yasutora), better known as Chad (Chado), is one of Ichigo's friends at school. He is a biracial Japanese/Mexican student who towers over his classmates. Despite his imposing appearance he is quite meek, and refuses to fight unless it is for the sake of another. Chad does not have awareness of ghosts at first, but this changes when he witnesses a group of children being attacked by a hollow. He discovers a unique ability that strengthens and armors one of his arms, enabling him to fight hollows. He later develops the ability to shoot energy from his armored arm. Hiroki Yasumoto voices him in the Japanese series Jamieson Price in the English adaptation.

Quincy (Kuinshī) are a clan of humans who, over many centuries, became spiritually aware. In doing so they devised their own brand of spiritual powers; they can absorb spiritual energy and then manipulate for offensive purposes. They most commonly reshape spiritual particles into various types of bow and arrows, but can also concentrate spiritual energy into the form of swords or explosives. At their height, Quincies used their powers to combat the hollows, protecting the inhabitants of the human world with a success rate greater than that of the Soul Reapers. Unlike the Soul Reapers, who purify the souls of hollows allowing them to rest in peace, Quincy destroyed the hollow, soul and all. This created an imbalance between the worlds of the living and the dead, threatening to destroy the universe. To prevent this, the Soul Reapers almost exterminated the Quincy, leaving only two Quincy to survive into the current Bleach storyline and creating a great animosity between the two groups. Tite Kubo created the Quincy as rivals to the Soul Reapers, resulting in long-range weapons as a counter to the standard Soul Reaper zanpakuto and white clothing as an antithesis to the black Soul Reaper uniform.

Soul Reapers are the protectors of souls, granting them access to Soul Society and keeping them safe from hollows. Many of the protagonists introduced in the series are Soul Reapers, either in profession, origin, or abilities. Each Soul Reaper possesses a zanpakutō a sword that doubles as both a weapon and a physical manifestation of the owner's soul. Each zanpakutō has its own personality, which is at times at odds with its owner's. Though Soul Reapers make up the bulk of the characters from Soul Society that have been introduced in the series, a far greater number of souls occupy its outskirts. More, Captains, Lieutenants