- The hero and protagonist, Harry is a twelve-year-old boy with messy hair and glasses who became famous within the wizard community by surviving the curse of a powerful wizard. Harry frequently finds himself entangled in dangerous adventures but he always lives to tell the tale. Harry's character represents good intentions, innocence, and the fantasies of childhood.
in-depth analysis of Harry Potter.
- Ron is tall, red-haired, and from a respected but poor family. Ron is one of Harry's two best friends at Hogwarts. He is loyal to Harry, and belligerent to their enemy, Malfoy. Ron uses experience and a process of trial-and-error to solve most mysteries. Ron's character is often overshadowed by Harry's, but Ron always manages to succeed.
in-depth analysis of Ron Weasley.
- Hermione is always the top student in her class. She is clever and well-read. Most spells come easily to her and remain in her encyclopedic mind. In this story especially, she throws her heart into fighting for causes, and she proves to be exceptionally loyal to Harry.
in-depth analysis of Hermione Granger.
- Once a student named Tom Riddle who attended Hogwarts fifty years before Harry, Voldemort became the most powerful dark wizard ever. When Harry was a baby, Voldemort killed Harry's parents and tried to kill Harry, only to have his curse backfire and render him powerless. He is an embodiment of pure evil. Through the help of Wormtail and a mysterious supporter at Hogwarts, Voldemort manages to rise again at the end of this story.
- Voldemort's original name, and the name of his Muggle father.
- Harry's loyal and loving godfather, and an unregistered animagus who can change himself into a large black dog, Padfoot, at will. He is widely thought to be responsible for thirteen deaths that, in reality, Peter Pettigrew caused, and since his name is not yet clear, he must remain in hiding. He fulfills his godfatherly duties in this book, looking carefully after Harry.
- The gamekeeper at Hogwarts and a good friend of Harry's, Hagrid is an enormous, caring, hairy man with an inimitable accent and a half-giant heritage. He has a great liking for strange and dangerous creatures, and in this book, he teaches Care of Magical Creatures.
Peter Pettigrew, or Wormtail
- Wormtail betrays Lily and James Potter, turning their whereabouts over the Voldemort, then blowing up a dozen Muggles, framing Black and turning himself into a rat so that he could escape. He now resides with Voldemort and ultimately sacrifices his right hand to facilitate Voldemort's rebirth.
- Dumbledore, the headmaster of Hogwarts, is a wise, powerful, elderly man with a long silver beard, and he is one of the most impressive characters Harry has ever met. He has a calm, secretive demeanor and is extremely intuitive, tolerant, and trustworthy, and he is the only wizard Voldemort has ever feared.
- A grizzled, eccentric, skilled retired Auror (dark-wizard catcher) who comes to teach Defense Against the Dark Arts at Hogwarts. He is deeply wary of anyone who could be a Dark wizard, and he drinks only from his hip flask. He takes a liking to Harry and subtly helps him with his tasks. In the end, he is really young Barty Crouch, disguised as Moody.
- The head of Magical Games and Sports within the Ministry of Magic; an ex- professional Quidditch player, and a rosy-faced, good-natured, irresponsible man, who once was a Death Eater, but without fully understanding his role.
- A nosey, middle-aged reporter who buzzes around, absorbing gossip to use in her reputation-ruining articles; Rita is an unregistered animagus beetle.
- The stiff and rule-abiding Head of the Department for International Magical Cooperation; Percy Weasley's boss.
Bartemius Crouch, Jr.
- Mr. Crouch's son, a convicted Death Eater who was allowed to remain outside of prison so long as he wore an Invisibility cloak and stayed in his father's house, guarded carefully by Winky. He escapes the confines of his father's house, returns to Voldemort, and comes to Hogwarts disguised as Moody.
- The Divination Professor; an insect-like, rather dramatic women who loves predicting deaths but is not at all accurate in her predictions.
- The head of Gryffindor House, a stern but deeply concerned witch, and a great aficionado of Quidditch.
- The Potions teacher, and a slimy, ill-tempered man, Snape is the head of Slytherin House and gets great pleasure out of trying to get Harry into trouble. He once was a Death Eater, but now Dumbledore trusts him as one of the good wizards.
- The headmaster of Durmstrang School, and a shifty and suspicious man; he was once a Death Eater, and he flees at the end of this story.
- The enormous and elegant headmistress of Beauxbatons, and the object of Hagrid's affection.
- The Triwizard champion for Beauxbatons, Fleur is a beautiful, silvery haired, part-Veela girl, who is a bit patronizing and snobby, but in the end grows moderately fond of Harry and Ron.
- Krum is the eighteen-year-old Bulgarian Quidditch Seeker, a boy-wonder who attends Durmstrang and is chosen as their Triwizard champion. He is quiet and sullen, but he develops quite a crush on Hermione, and he turns out to be a nice, competent individual.
- The handsome, brave, and fair Hufflepuff Triwizard champion; dies at the hands of Lord Voldemort.
- A pretty fifth-year Ravenclaw girl on whom Harry develops a crush.
- A sweet, pudgy, and very clumsy boy who lives with Harry in Gryffindor. He lives with his grandmother because his parents, it turns out, were tortured and driven mad by Death Eaters.
- Lupin is a werewolf and was last year's Defense Against the Dark Arts teacher.
- The Defense Against the Dark Arts teacher during Harry's first year at Hogwarts; he was possessed by Voldemort, and he ultimately died.
- A slimy, smirking, and snotty boy from Slytherin House, Malfoy is Harry's greatest Hogwarts nemesis (not counting Voldemort, who usually resides outside Hogwarts). Because his family is very wealthy and influential, Malfoy often tries to use his father's power as an intimidation tactic.
- Draco Malfoy's father, a mean, powerful man whose name and money his son, Draco, uses to get his way.
- Ron's younger sister, and a sweet and shy red-haired girl with an enormous crush on Harry.
- Ron's somewhat pompous older brother who currently works for the Ministry of Magic, under Mr. Crouch.
- One of Ron's older brothers, Fred is a beater for the Gryffindor House Quidditch team, and a troublemaker when paired with his twin brother, George. Fred has the slightly louder, more over-the-top sense of humor of the two, but they are identical and usually inseparable. He and his brother George are currently involved in trying to set up a line of practical jokes called Weasleys' Wizard Wheezes.
- One of Ron's older brothers, George is a beater for the Gryffindor House Quidditch team, and a troublemaker when paired with his twin brother, Fred. He is somewhat subtler and more tongue-in-cheek than his twin, but otherwise, for the most part identical. Together, the Weasley twins are an infamous, amusing, and charming pair.
- Ron's second eldest brother, who was a prefect and Head Boy at Hogwarts, and who has a ponytail and an earring, and works in Gringotts Bank in Egypt.
- The eldest Weasley offspring who currently works with dragons in Romania, and who comes to Hogwarts to help with the first task.
- Ron's mother; she is very maternal and protective, but also quite strict.
- Ron's father, who works in the Misuse of Muggles Artifacts Office within the Ministry of Magic. He loves any sort of Muggle things with a buoyant, childlike enthusiasm. A thoroughly likeable man, Mr. Weasley treats Harry as if he were one of his own (many) children.
- Once Mr. Crouch's house-elf, and now a free elf working at Hogwarts, she is a squeaky, hysterical, unconfident figure.
- Once the Malfoys' house-elf, Dobby was freed by Harry several years ago, and now is working at Hogwarts and feeling quite liberated with his new freedom. He is very loyal to Harry.
- Harry's stuffy, nasty-tempered Muggle uncle.
- Harry's unpleasant Muggle aunt.
- Harry's spoiled, overweight Muggle cousin.
- The Riddles' gardener, and an elderly, misanthropic Muggle suspected to have murdered the Riddles; Frank is murdered by Voldemort in the first chapter of the book.
- A middle-aged, gossipy witch who works for the Ministry of Magic. She is tapped for information and killed by Voldemort.
- The proud father of Cedric, and another worker for the Ministry of Magic.
- Harry's mother who sacrificed herself to save Harry from Voldemort; she and James Potter return as ghosts to protect Harry from Voldemort at the end.
- Harry's father, also killed by Voldemort.
- The Hogwarts caretaker, who is grouchy and adores nothing but his cat.
- The rather eccentrically dressed Minister of Magic, very kind to Harry, but ultimately somewhat of a stubborn and cowardly man, when he refuses to acknowledge Voldemort's return.
- One of Harry's Gryffindor roommates
- Another of Harry's Gryffindor roommates.
- A pretty but rather vain and annoying Gryffindor girl who goes to the Yule Ball with Harry.
- A third-year Gryffindor boy who idolizes Harry.
- One of Draco Malfoy's unintelligent, lumbering cronies.
- The other of Draco Malfoy's unintelligent, lumbering cronies.
- A friendly Gryffindor ghost.
- A poltergeist who causes lots of harmless trouble at Hogwarts.
- A glum Hogwarts ghost who has somewhat of a crush on Harry.
- A confused Muggle who owns the site where the Weasleys camp during the Quidditch World Cup.
- Harry's snowy, loyal owl.
- Ron's tiny, excitable pet owl.
- Hermione's aggressive ginger cat.
- Dumbledore's beautiful pet phoenix, who gave a two feathers that ended up in the wands of Harry and Voldemort.