- Maddie Fenton: The mother of the Fenton family. Maddie is very intelligent and loves her family very dearly. She and Danny were very close when he was little. Out of the two Fenton parents, she seems to be the one that takes control of the situation, and seems to be a rational person, although she does jump to conclusions often.
- Jack Fenton: The father of the Fenton family. He is overly obsessed on the topic of ghosts. He may be a brawn, but he is smart like his wife and has invented numerous gadgets, like the Fenton Thermos. He may be smart but he has a lousy shot and can be quite random and clumsy. Jack tends to favor Jazz and calls her "Princess."
- Jazz Fenton: The daughter and the elder of the Fenton children. She believes she is the mature and sane one of the family, but she loves them all the same. Growing up, she took care of Danny when their parents were too busy with their work and has become over-protective of him. Jazz and Danny form a tighter bond when she reveals that she knows his ghostly secret.
- Danny Fenton: The youngest Fenton and the main character of the series. Danny is very warm-hearted and sometimes childish, but he can act mature when the need arises. When his parents created the Fenton Portal, Danny gained ghostly powers, which he kept secret from his family because he thought they wouldn't understand. Eventually his sister learns about them in "My Brother's Keeper," and his parents in "Phantom Planet."
- Alicia: Maddie's biological sister. She was divorced to an unnamed ex-husband, Danny and Jazz's ex-uncle.
Danny’s maternal grandfather Danny’s maternal grandmother │ │ │ │ └────────┬─────────┘ │ ┌──────────────────│─────────────────┐ │ │ │ │ Jack Fenton────────Maddie Fenton Vlad Plasmius Alicia │ │ │ │ ┌────────┴─────────┐ ┌────────┴─────────┐ │ │ │ │ Danny Fenton Jazz Fenton Dani Phantom Clones of Danny
Jack and Maddie dated during their college years, and did research together on ghosts. They created a proto-portal, along with their friend, Vlad Masters, but there were miscalculations in its design and it infected Vlad with ecto-acne, giving him ghost powers. They wouldn't see Vlad again for another 20 years.
Soon after college, Jack and Maddie got married and had two kids, Jazz and Danny. Although they loved their children deeply, the couple sometimes put their ghost-hunting careers before their family. Because of this, Jazz often had to fend for herself and her little brother, which would put distance between them and their parents as they grew up.
Around the time that Danny entered high school, Jack and Maddie completed their Fenton Portal, but it didn't work at first. After accidentally activating it by pressing the "On" button, Danny obtained his ghost powers and became half-ghost. Throughout the next few years, the Fentons faced situations that both challenged and strengthened their family dynamic, mostly due to ghost-hunting and Danny's new persona as Danny Phantom. On the several occasions that Danny's secret was revealed, his parents ultimately accepted his half-ghost status (Jazz having done so early on in "My Brother's Keeper"). When they learned his secret for good in "Phantom Planet," the family became closer than ever.
Due to their peculiar interest in ghosts, most people outside of their immediate group view the Fentons as odd, which has even affected Danny and Jazz's reputations at school. Some people, such as Sam and Tucker's parents, see Jack and Maddie as dangerous because of their careers, and thus try to limit interaction with the Fentons. While eccentric, the Fentons are known for being reputable ghost hunters in the town's eye, and are often called on to be advisers for ghost-related policies.
- In an alternate timeline, Jack Plasmius mentions his cat, Jasmine, and remarks that he thinks the name "Danny" is dumb, revealing that it was probably Jack who named Jazz and Maddie who named Danny.
- Throughout the series, Jack is the only member of the Fenton family who has referred to Danny as "Daniel."
- Aside from being a pun on "phantom" for Danny to bear the alias of his hero persona, the name "Fenton" is an actual surname, meaning "a town of marsh."
- If the series continued beyond Phantom Planet, Dani Phantom would've been adopted by Jack and Maddie as their daughter and joined their family.
|Groups and Organizations in Danny Phantom|
|Ghost hunters||Amity Park Ghostkateers | Fenton family | Masters' Blasters | Team Phantom | The Extreme Ghostbreakers | The Groovy Gang and Scaredy Cat|
|Law and government||Ghost Zone Police Department | Guys in White|
|Miscellaneous||Dumpty Humpty | Ember's ghost band|