Tanjiro Kamado
Tanjiro Kamado is the main protagonist of Demon Slayer: Kimetsu no Yaiba. He is a Demon Slayer in the Demon Slayer Corps, who joined to find a remedy to turn his sister, Nezuko Kamado, back into a human and to hunt down and kill demons, and later swore to defeat Muzan Kibutsuji, the King of Demons, in order to prevent others from suffering the same fate as him.
Before he became a Demon Slayer, Tanjiro was a coal burner before his entire family was slaughtered by Muzan while his younger sister, Nezuko, was turned into a demon.

Zenitsu Agatsuma
Zenitsu Agatsuma is one of the main protagonists of Demon Slayer: Kimetsu no Yaiba and along with Inosuke Hashibira, a travelling companion of Tanjiro Kamado and Nezuko Kamado. He is also a Demon Slayer in the Demon Slayer Corps.

Inosuke Hashibira
Inosuke Hashibira is one of the main protagonists of Demon Slayer: Kimetsu no Yaiba and along with Zenitsu Agatsuma, a traveling companion of Tanjiro Kamado and Nezuko Kamado. He is also a Demon Slayer in the Demon Slayer Corps.

Kanao Tsuyuri
Kanao Tsuyuri is a major supporting character of Demon Slayer: Kimetsu no Yaiba. She is a Demon Slayer of the Demon Slayer Corps, Shinobu Kocho's Tsuguko and the adopted sister of Shinobu and Kanae Kocho.

Genya Shinazugawa
Genya Shinazugawa is a major supporting character of Demon Slayer: Kimetsu no Yaiba. He is a Demon Slayer in the Demon Slayer Corps and also the younger brother of the Wind Hashira, Sanemi Shinazugawa.

Giyu Tomioka
Giyu Tomioka is a major supporting character of Demon Slayer: Kimetsu no Yaiba. He is a Demon Slayer of the Demon Slayer Corps and the current Water Hashira.

Shinobu Kocho
Shinobu Kocho is a major supporting character of Demon Slayer: Kimetsu no Yaiba. She is a Demon Slayer of the Demon Slayer Corps and the current Insect Hashira.
Shinobu Kocho is also the younger sister of Kanae Kocho along with her adoptive younger sister Kanao Tsuyuri. After a demon killed her parents, Shinobu joined the Demon Slayer Corps along with her sister in order to protect others from suffering the same fate as her.

Kyojuro Rengoku
Kyojuro Rengoku was a major supporting character of Demon Slayer: Kimetsu no Yaiba and a major character in the Mugen Train Arc. He was a Demon Slayer of the Demon Slayer Corps and the late Flame Hashira.

Tengen Uzui
Tengen Uzui is a major supporting character of Demon Slayer: Kimetsu no Yaiba and a major character in the Entertainment District Arc. He was a former member of the Demon Slayer Corps, standing as the previous Sound Hashira (音おと柱ばしら Oto Bashira?).

Muichiro Tokito
Muichiro Tokito is a major supporting character of Demon Slayer: Kimetsu no Yaiba. He is a Demon Slayer of the Demon Slayer Corps and the current Mist Hashira.
Muichiro along with his brother Yuichiro Tokito, are also the descendants of Upper Rank One, Kokushibo.

Mitsuri Kanroji
Mitsuri Kanroji is a major supporting character of Demon Slayer: Kimetsu no Yaiba. She is a Demon Slayer of the Demon Slayer Corps and the current Love Hashira.

Sanemi Shinazugawa
Sanemi Shinazugawa is a major supporting character of Demon Slayer: Kimetsu no Yaiba. He is a Demon Slayer of the Demon Slayer Corps and the current Wind Hashira.
Sanemi is also the older brother of Genya Shinazugawa, a Demon Slayer who fought alongside Tanjiro Kamado and Nezuko Kamado. Before becoming a Hashira, Sanemi, along with his partner Masachika Kumeno, defeated the former Lower Rank One, Ubume, with Masachika dying as a result.

Obanai Iguro
Obanai Iguro is a major supporting character of Demon Slayer: Kimetsu no Yaiba. He is a Demon Slayer of the Demon Slayer Corps and the current Serpent Hashira.

Yoriichi Tsugikuni
Yoriichi Tsugikuni is a major supporting character of Demon Slayer: Kimetsu no Yaiba. He is a legendary Demon Slayer who lived nearly 500 years ago during the Sengoku Era (the Golden Age of Demon Slayers), as well as the strongest Demon Slayer to have ever existed. He is also the inventor of Breathing Styles, being the one who created the first ever Breathing Style that would eventually become the Hinokami Kagura used by Tanjiro Kamado and members of the Kamado Family.
Yoriichi is the younger twin brother of Michikatsu Tsugikuni, who later became a demon and joined the Twelve Kizuki.