Vincent Chase (Adrian Grenier)
- "I got into this business so I wouldn't have to work."
A pretty boy with who we're told is a decent actor. Vince has co-dependency issues and is a notorious womanizer. Never goes anywhere without one of his "boys".
- Ambiguously Brown: In real life Adrian Grenier is half Mexican and part Indian but Vince's full ethnic origins are never explained. In one episode, he claims his grandfather is Japanese while in another episode he says he is part Italian. He has also claimed to be Irish. When preparing to play Pablo Escobar in a biopic he says that he fits the role because he is part Hispanic.
- Author Avatar / Expy: Of Mark Wahlberg
- Beard of Sorrow: Vince grows one after Medellin flops.
- Brainless Beauty: Let's face it, the guy's a total mimbo.
- Brilliant, but Lazy: Several characters have said that Vince is a talented actor, but began phoning in his performances and relying too much on his good looks and name after he achieved his early success.
- The Casanova: Vince is rarely unsuccessful in his attempts to seduce women.
- Doing It for the Art: In-universe. Vince frequently states that he doesn't need the fame or fortune, and would rather do a low budget film that he's passionate about (Such as Queen's Boulevard or Medillin) over a forgettable film that would provide a fat paycheck; and had no interest in Aquaman until James Cameron signed on as director.
- Drugs Are Bad: In Season 7 Vince develops a drug problem while dating real-life porn star Sasha Grey. Vince's friends end up staging an intervention and convincing him to go to rehab.
- Heterosexual Life-Partners: With E.
- Informed Ability: We are told Vince is a good actor, though we rarely see him acting. The few occasions we do, it's hard to tell because we have no frame of reference for his performance.
- It's All About Me: Many times he will make a decision without any regard to how it affects other people.
- Mr. Fanservice
- Ungrateful Bastard: Has a few instances of this towards E, such as getting upset that E got sick of Vince treating him like his manager despite Vince's own refusal to hire E in the role.
- What the Hell, Hero?: The situation is usually resolved when Vince expects Drama & Turtle to back him up, only for them to side with E.
Eric "E" Murphy (Kevin Connolly)
Vince's best friend since childhood, who takes on the role of his manager (unofficially, then officially). Eric is just about as co-dependent as Vince, but slightly more self-aware. Less of a womanizer, he's more of a serial monogamist.
- The Chick: E has shades of this. He has a tendency to get too attached in relationships.
- Expy: Of Mark's manager Eric Weinstein.
- Heterosexual Life-Partners: With Vince.
- In Love with Love: Vince even comments once that E likes to fall in love at the drop of a hat.
- In Name Only: An in-universe inversion - throughout the first season, E is constantly treated as Vince's manager by everyone, even though Vince refuses to actually hire him as such, which essentially made "I'm/He's not his/my manager." into Vince & E's catchphrase.
- Naïve Newcomer: Most of the time Ari gets mad at E because the latter doesn't understand how the business side of Hollywood works.
- Office Romance: E begins managing Anna Faris (playing herself, of course) after getting into a fender-bender with her. He quickly becomes infatuated with her and indirectly causes her to break up with her boyfriend. She fires him as her manager because of his feelings for her as well as his personal dislike for a script she was offered.
- Relationship Revolving Door: With Sloan, over and over again.
Johnny "Drama" Chase (Kevin Dillon)
- "I've been working steady for the past 12 years, minus the last 3."
Vince's older (half)brother, who's been in the acting biz longer, but with not nearly as much success. Goes by "Drama" because well, he's a bit of a basket case.
- Big Brother Instinct: Drama is very protective of his "baby bro" Vince, and is always willing to help whenever Vince is in trouble.
- Casanova Wannabe: Drama considers himself to be a real ladies' man, but more often than not we see him getting rejected.
- The Chick: Drama has shades of this and is overly dramatic.
- Expansion Pack Past: Drama has a story about anyone/everyone in Hollywood, but somehow none of the other guys have heard them before.
- Expy: Of Mark's cousin Johnny "Drama" Alves.
- Old Shame: An in-universe subversion; it turns out Drama loves the cult status of what should be an Old Shame - Viking Quest.
- Team Chef: Drama is such a good cook that Vince has actually hired him as his personal chef. In one episode, he buys a condo specifically because he loves the kitchen so much.
Salvatore "Turtle" Assante (Jerry Ferrara)
- "This is where you should be living, Vince. In a kingdom, like a prince."
Another of Vince's friends from childhood, but often hangs out with Drama. Came to Hollywood to act as Vince's driver, he enjoys being a hanger on with the least amount of guilt out of the three. At least for a while.
- Character Development: Initially, he's content to spend his life as Vince's gofer/driver and enjoy the spoils that come with it. Later on, after maturing a bit, he realizes he wants to be more self-sufficient and begins the path of becoming a business mogul.
- Drunken Master: A variation on the trope; Turtle is only good at video games when he's high on marijuana.
- Expy: Of Mark's late assistant Donnie "Donkey" Carroll.
- The Load: At least until Character Development kicks in.
- Only Known by Their Nickname: His first name isn't revealed until season five and his last name in The Movie.
- Pretty Fly for a White Guy: In one episode, Turtle even chastises drama by saying "Do you have to act so white?"
- Rags to Riches: Goes from mooching off Vince to becoming a multi-millionaire by the time of the film.
Ari Gold (Jeremy Piven)
- "Call me Helen Keller because I'm a fucking miracle worker!"
Vince's agent, a foul-mouthed, ruthless businessman, responsible for much of Vince's success. Although his demeanor can be off-putting, he's one of the most popular characters on the show, and has proven time and time again that he truly cares for Vince beyond just his career.
- The Ace: Ari may not be nice, but he's so good at his job that he's become the most powerful and influential agent in Hollywood.
- Bad Boss: Enjoys ripping his underlings with gusto...LLOYD!!!!
- Berserk Button: Ari's rude, arrogant and belligerent normally, but the things that will truly make him angry are double-crossing him, questioning his word or disrespecting his family.
- Expy: Of real-life Hollywood agent Ari Emmanuel.
- Happily Married: Ari is quite devoted to his wife and insists that he has never cheated on despite having many opportunities. When she leaves him in the show's final season, he is absolutely crushed and falls into a depression.
- Hot-Blooded: To put it mildly.
- Jerkass: A racist, homophobic, sexist, short-tempered, unpleasant ASSHOLE
- Jerk with a Heart of Gold: Ari Gold actually cares a lot about those around him, and will save many an employee from getting fired by Babs. On top of that, he's clearly devoted to his wife & children. He also genuinely cares about Vince, and is devastated when Vince fires him at one point.
- Indy Ploy: Very good at thinking on his feet.
- Married to the Job: Hollywood is a harsh and demanding mistress.
- No Indoor Voice: His default setting is loud, and it only gets louder from there.
- Old Flame: Dana Gordon, whom he had a relationship with before he met his wife. In the final season, Ari and Dana tempoarily rekindle their romance after Ari's wife leaves him. But Ari breaks up with Dana after realizing that he's still in love with his wife.
- Pet the Dog: He's a friend of his friends and a devoted family man.
- Smug Snake: He is as arrogant as competent.
Lloyd Lee (Rex Lee)
Ari Gold's much put-upon assistant.
- My Master, Right or Wrong: Loyally devoted to Ari, with punctual exceptions.
- Took a Level in Badass: Becomes a competent agent on his own.
'''Melissa "Mrs. Ari" Gold (Perrey Reeves)
Ari's long-suffering wife and the mother of his children. She is one of the few people not intimidated by Ari's personality and is shown to be quite capable of standing up to him. She is also a trust fund baby and former soap opera actress.
- Happily Married: Although they sometimes argue, Mrs. Ari is shown to be supportive of her husband and willing to stand by him through thick and thin. Until the final season, when she decides that she's had enough of her husband putting his job before his family and leaves him. Thankfully, the two of them reconcile.
- Housewife: Has no job (although she used to be an actress) and spends her time raising her children and working for various charities.
- No Name Given: For most of the show's run, she was referred to only as "Mrs. Ari" or "Ari's wife." In the final season we learn that her first name is Melissa.
- Old Shame: An in-universe example. In Season 5 it's revealed that she once starred in an erotic movie.
Sloan McQuiewick (Emmanuelle Chriqui)
E's on again, off again girlfriend. In the final season she becomes pregnant with E's baby, and the two of them fly off to an unknown location.
- Has a Type: In her first appearance she mentions that she doesn't date actors.
- Prenup Blowup: When E and Sloan become engaged, Sloan's father insists that E sign a prenupual agreement that will prevent him from getting any of Sloan's family fortune if the two of them get a divorce. E is insulted by the idea of signing a prenup and the fact that Sloan sides with her father eventually leads to them breaking off the engagement.
- Ugly Guy, Hot Wife: Average guy, hot girlfriend: Shortly after Sloan and E begin dating, Ari comments to E that "Sloan is way too hot for you."
- Will They or Won't They?: E and Sloan break up and get back together multiple times during the course of the show. When they finally get back together at the end of the final season not many people were surprised.
Billy Walsh (Rhys Coiro)
An acclaimed independent film director whose work includes two movies starring Vincent Chase (Queens Boulevard and Medellin)
- Bad Boss: During the filming of Medellin Walsh becomes increasingly unhinged and terrorizes the cast and crew of the film.
- Creator Killer: An in-universe example. Medellin ends up being such a terrible movie that it kills Walsh's career as a film director. In season 7 he comes to Vince and the gang looking for work, and becomes the director of an animated television series called Johnny's Bananas.
- HeelFaith Turn: Walsh returns in Season 7 after a two year absence, and we learn that he has spent those years turning his life around and trying to become a better person. In fact, he has even become an ordained minister.
- Jerk with a Heart of Gold: When Medellin is booed at its premiere, Walsh stands up and angrily chastises the crowd for being disrepectful to the cast and crew who worked on it.
- No Celebrities Were Harmed: According to the season 2 commentary, Billy Walsh was based on Entourage writer Rob Weiss as well as actor/director Vincent Gallo.