- Yusuke Urameshi (浦飯幽助, Urameshi Yūsuke) is a student, attending the fictional Sarayashki Junior High School. His poor attendance, constant fighting, and bad habits such as drinking and smoking have earned him the label of delinquent among most of his teachers and classmates. This all changes rather abruptly as Yusuke is struck by a car and dies, while trying to save a small child who had wandered into the road to retrieve a ball. Such an altruistic deed catches the Underworld by surprise. As they don't have a place for him yet in heaven or hell, Yusuke is permitted to undergo an ordeal which could let him return to his body and resume his life. However, in an unexpected turn of events, it is revealed that Yusuke has a particularly strong aura and fighting spirit, which is why Koenma, the son of Enma, Lord of the Underworld, recruits him as Spirit Detective, charged with investigating supernatural phenomena in the human world and capturing criminals dealing in underworld crime. Yusuke bears quite a bit of affection for his childhood friend, Keiko Yukimura, who initially takes a role as Yusuke's conscience, making sure he comes to class and behaves, and later as his romantic interest. Yusuke was raised by his single mother, Atsuko, who finds time to drink and party throughout the story.
- Kazuma Kuwabara (桑原 和真, Kuwabara Kazuma) is a student at the fictional Sarayashiki Junior High School. He is noted as the "second toughest punk at Sarayashki", despite his unusual affinity for kittens. He is constantly picking fights with Yusuke, to prove that he is tougher than him, but never succeeding. Eventually Kuwabara's feelings of anger toward Yusuke become feelings of respect. Kuwabara has a very advanced sixth-sense, though not as acute as his older sister Shizuru's. Yusuke uses this to his advantage in his attempt to return to life. Kuwabara ends up assisting in most of Yusuke's cases, gaining power over his own aura which he wields in the form of an Aura Sword (霊剣, Rei Ken). While assisting Yusuke during an early case, in Tarukane's mountain compound, he meets the ice apparition Yukina and instantly falls in love with her. Yukina is very grateful to Kuwabara for his role in saving her from captivity, but seems oblivious to his feelings of affection. As the story progresses Kuwabara becomes more engrossed in his studies, choosing to cram for his high school exams rather than follow Yusuke and the others into the Demon plane.
- Kurama (蔵馬) is a demon thief who, after being fatally wounded, fuses with the unborn child of Shiori Minamino . He is born as Shuichi Minamino (南野 秀一, Minamino Shūichi), a human, though he retains his demon powers at a much lower, D-class energy level. Kurama had originally planned to return to his demon form after regenerating his powers; however, while he has an accident, his mother saves him; injuring herself in the process. This forms a bond of love and loyalty which, despite his intention to deceive and abandon her, Kurama cannot bear to break and thus, he chooses to stay as Shuichi to keep Shiori happy. He attends the fictional Meioh Private Academy (私立盟王学園) where his grades are among the top in his year. During the Dark Tournament Kurama is temporarily reverted back to his original form, the Demon Fox. Kurama uses his aura to control plants, including his signature weapon, a rose he keeps in his hair which he turns into a whip of thorns capable of cutting through steel. He also possesses a skill for strategic, analytical thinking which allows him to gauge his opponents' strengths and weaknesses and to formulate effective strategies. As the Demon Fox, his powers are far greater and he is capable of creating demonic plants which possess various deadly attributes and highly formidable powers.
- Hiei (飛影) is a male fire demon born to a race of female Ice Demons. The Koorime or Ice Maidens reproduce every 100 years asexually, always giving birth to a female. A male child is born only if the Maiden has had sex with a male, which is forbidden in their society. Hiei and his twin sister, Yukina, were born to the Ice Maiden Hina. As her children were born, Hina wept two tears which crystallized into Hiruseki stones and were given to the babies. Hiei was thrown from the floating Ice domain to his supposed doom. He does manage to survive, though, and grows up in the wilderness where he develops a thirst for killing. The only time he finds peace is looking at the tear from his mother. He soon decides to find the ice domain and take revenge on the women who cast him out. During a battle his tear stone is lost and, realizing he must now find the stone as well as the Ice Domain, Hiei goes to the Demonic Osteopath, Shigure, and has the Dark Eye (referred to as the Jagan Eye in the English anime dub) implanted in his forehead which gives him many powers, including hypnosis, telepathy, and clairvoyance or remote viewing. Even with the Dark Eye Hiei cannot find his tear stone, though he easily finds the ice domain. When he gets there he finds his mother's grave and his lust for revenge fades. He is told his twin sister has run away and decides to search for her as well. Hiei wields a sword, has superhuman speed and can produce and control fire. During the Dark Tournament he taps into the unruly fires of hell, known as the Dark Flame of the Overlord, which he eventually masters.
- Genkai (幻海) is an elderly martial arts expert who lives alone in a very large temple. She first appears during Yusuke's second case as he infiltrates a tournament she is holding to find a successor to her techniques in search of the demon Rando. Genkai is a legendary reiki master, known both in the human and demon realms. Yusuke ends up winning the tournament, defeating Rando in the process, and is taken on as a student by Genkai. When she was 50 years younger, Genkai and the younger Toguro brother were lovers and teammates in an earlier Dark Tournament. After winning, Toguro decides to become a demon, while Genkai returns to the human world, creating a split in their relationship. She enters the next dark tournament with Yusuke, disguising herself as the "Masked Fighter" in order to once again face Toguro. Her signature technique is the Spirit Wave, an outpouring of spirit energy from the whole body which can be directed through several different variations. This makes her technique effective in healing and purification, in addition to combat. A side effect of using this power is a shifting of the body's cells which leads to a temporary reversion to the form in which the wielder was at their most powerful in life. In Genkai's case, it allowed her to briefly regain her youth.
- King Enma Jr., usually addressed as Koenma (コエンマ) is the son of spirit realm ruler King Enma, and the one who takes responsibility of his father's work when he's away. Koenma usually appears as a toddler with a pacifier in his mouth, though he is said to be at least 700 years old. He can also transform into a young adult form, retaining his pacifier and the letters "Jr" on his forehead. Koenma acts as Yusuke's boss, assigning his cases. His pacifier is a receptacle, which Koenma constantly imbues with his spirit energy. It can create a powerful barrier which Koenma states is to fend off a dark evil sometime in the future.
- Team Urameshi vs. Teams on the Boat - Win
vs. Team Rokuyukai
- Kuwabara vs. Rinku - Loss
- Kurama vs. Roto - Win
- Hiei vs. Zeru - Win
- Yusuke vs. Chu - Win
- Final Result: Win
- Yusuke, Kuwabara, Masked Fighter vs. Dr. Ichigaki Team - Win
- Final Result: Win
vs. Team Masho
- Kurama vs. Gama - Win
- Kurama vs. Toya - Win
- Kurama vs. Bakken - Loss
- Yusuke vs. Bakken - Win
- Yusuke vs. Jin - Draw
- Kuwabara vs. Risho - Win
- Final Result: Win
vs. Team Uraotogi
- Hiei vs. Makintaro - Win
- Hiei vs. Kuro Momotaro - Win
- Kurama vs. Ura Urashima - Win
- Kuwabara vs. Shishiwakamaru - Loss
- Masked Fighter vs. Shishiwakamaru - Win
- Kuwabara vs. Onji - Loss
- Genkai vs. Suzuki - Win
- Final Result: Win
- Kurama vs. Karasu - Loss
- Hiei vs. Bui - Win
- Kuwabara vs. Elder Toguro - Win
- Yusuke and Koenma vs. Younger Toguro and Sakyo (Koenma and Sakyo each bet their lives on their teammate's victory) - Double Win
- Final Result: Win
|e v||Team Urameshi|
|Members:||Yusuke Urameshi | Kazuma Kuwabara | Kurama | Hiei | Koenma | Genkai|