A boy living on Destiny Islands. He is best friends with Riku and Kairi. He has a cheerful, unshakable heart and a strong sense of justice, though his tendency to be a bit of a goofball is his one flaw. His Keyblade is the "Kingdom Chain." He has a simple and clear personality, not worrying much about details or complex matters. Because of this, he has been targeted by evil forces, but each time, Sora has overcome them through the strength of his connected heart. Among the Keyblade wielders appearing in the story, he is the only one who did not inherit a Keyblade from another wielder and lacks the innate power of one. Therefore, when Riku, who received the formal Rite of Succession, is nearby, the "Keyblade of the Realm of Light" that Sora holds will return to Riku's hand.

A boy with slightly long silver hair and blue-green eyes. He lives on Destiny Islands. He is one year older than Sora, and is both his best friend and rival. His Keyblade is "Way to the Dawn." While he appears mature, games like Kingdom Hearts 3D [Dream Drop Distance] show a side of him more appropriate for his age. He is incredibly muscular for his age, with very toned arms. As Sora's best friend and rival, he plays an active role as the other protagonist in COM and 3D.

The main heroine of the Kingdom Hearts series. A bright girl with striking short red hair. She is active and possesses a strong will and heart to face difficulties. Her Keyblade is "Destiny's Embrace." She drifted to Destiny Islands as a young child and has lost her memories from before then. Her hometown is Radiant Garden (later Hollow Bastion), but when the worlds were restored, she remained on Destiny Islands to wait for the two boys to return.

A girl Sora met at Castle Oblivion in Kingdom Hearts: Chain of Memories. She always carries a sketchbook, drawing her memories with Sora and the others. Her true identity is the Nobody of Kairi, one of the Seven Princesses. Members of Organization XIII and DiZ refer to her as a "witch" over memories. She does not possess the memories of her original self, Kairi. As a flawed Nobody born under special conditions, she was called the "most fleeting of shadows" and "a being that does not exist in the truest sense," and the Organization did not welcome her as a member.

A member of Organization XIII, Number VIII. Written as Axel. He often acts on his own will, separate from the Organization's motives. He has an elusive personality. His catchphrase is "Got it memorized?" He has been close to Roxas since he was assigned as his mentor during their time in the Organization. They shared a bond so deep they recognized each other as best friends, making it hard to believe they were heartless Nobodies. After his Nobody and Heartless (though the latter is not explicitly depicted) were destroyed in KHII, he was revived as a human. He begins to actively work as an ally to Sora and his friends.

A boy living in Twilight Town. He serves as the protagonist in KH2 and 358/2 Days. His true identity is Sora's Nobody, born when Sora became a Heartless. He is like a twin to Namine, Kairi's Nobody who was born using Sora's body and soul as a medium; however, Roxas was born in Twilight Town while Namine was born in Castle Oblivion. Because Roxas can wield a Keyblade just like his original self, he was recruited by Xemnas as Number XIII of the Organization shortly after his birth. He lacks the memories of his human life that Nobodies usually have, and was initially very dazed and quiet. Because of this, he followed the Organization without question. Like Sora, he has a cheerful and active personality, but there is a certain maturity to him. His Keyblades are "Oathkeeper" and "Oblivion."

Spelled "Xion." She appears starting in 358/2 Days. The 14th member of the Organization, a girl who joined a week after Roxas entered Organization XIII. She uses a Keyblade and her attribute is Light, both of which are the same as Roxas. Sharing a similar background of having no prior memories, she and Roxas became close friends. Later, they became friends with Axel as well, spending their days having idle conversations and eating ice cream while watching the sunset.

One of the protagonists of Kingdom Hearts Birth by Sleep. A young man and Keyblade wielder living in the Land of Departure. He is around 20 years old. He lives with Ven and Aqua as if they were siblings. He has a strong sense of justice and is honest and kind-hearted, but he is also extremely gullible. Aqua describes Terra as being "too pure." He is a hard worker who never forgets his pursuit of strength. His self-declared dream is to become a "Keyblade Master." His Keyblade is "Earthshaker."

One of the protagonists of Kingdom Hearts Birth by Sleep. She is the first female protagonist in the KH series. One of Master Eraqus's apprentices. She is a fellow student and close friend to Terra and Ventus. At the start of the story, she is the only one of the three chosen as a Keyblade Master and travels to investigate the changes in the worlds. The Final Episode, added after reaching the ending with all characters, features Aqua as the playable protagonist. She has a personality that is strong-willed yet flexible. Her Keyblade is "Rainfell."

One of the protagonists of Kingdom Hearts Birth by Sleep. A Keyblade wielder in training at the Land of Departure. He has a very curious and pure heart. His nickname is "Ven." He lost his memories from before coming to the Land of Departure and was taken in as an apprentice by Keyblade Master Eraqus. Since then, he lived with Terra and Aqua as a family while they trained together. Prompted by words spoken to him by Vanitas, he leaves the Land of Departure to travel across the worlds. His Keyblade is "Fresh Breeze."