- Liv Rooney (Dove Cameron) is a former television star, who is the identical twin sister of Maddie.
- Maddie Rooney (Dove Cameron) is the star of her school's basketball team, who is the identical twin sister of Liv.
- Joey Rooney (Joey Bragg) is the younger brother of the Liv and Maddie and older brother of Parker.
- Parker Rooney (Tenzing Norgay Trainor) is the younger brother of the twins and youngest sibling in the Rooney family.
- Karen Rooney (Kali Rocha) is the mother of the four children and the school vice principal for her twin daughters' and Joey's school.
- Ruby (Lauren Lindsey Donzis) is the cousin of the Rooney's and lives in California with her mother.
- Diggie Smalls (Ryan McCartan) is the school's boys basketball team captain. He was Maddie's boyfriend in Move-A-Rooney, until they broke up in Flugelball-A-Rooney.
- Willow (Jessica Marie Garcia) is Maddie's friend. She is on Maddie's basketball team and has a huge crush on Joey.
- Skippy Ramirez (Allen Alvarado) is Joey's best friend. He is a professional skateboarder.
- Skylar (Gabrielle Elyse) is Joey's crush. In Kang-A-Rooney it shows she is new. She's friends with Joey.
- Artie (Jimmy Bellinger) is Joey's nemesis. He is a member of their school's rocketry club.
- Johnny Nimbus (Kurt Long) is the Channel 4 meteorologist and the host of the cooking segment "Nibblin' With Nimbus". He is a fan of Liv's ex-boyfriend, Miller White.
- Evan (Carter Hastings) is Parker's 9-years-old best friend and sidekick. Parker helped him earn his blue belt in their karate class.
- Gemma (Chloé Wepper) is the producer of Liv's new show, Voltage, in Season 3.
- Holden Dippledorf (Jordan Fisher) is the Rooney's neighbour and he becomes Liv's new boyfriend in Coach-A-Rooney.
- Josh Willcox (Lucas Adams) is Liv's co-star of Voltage in Season 3. He becomes Maddie's new boyfriend in Vive-La-Rooney.
- Aunt Dena (Jolie Jenkins) is the Aunt of the Rooney's, the mother of their cousin Ruby and the sister of Karen Rooney (the mother of the Rooney kids).
- Bernard (Dwight Howard) is a personal trainer who started working for Joey after he won a raffle. He joined Maddie's basketball team.
- Kylie (Anne Winters) is a bad girl who likes ditching school and shop-lifting. Liv wanted to be her friend, much to Maddie's dismay.
- Miller White (Connor Weil) is a professional skateboarder. He is Liv's ex-boyfriend.
- Jenny Keene (Ella Anderson) is a self-centered little girl who performed with Liv in the Stevens Point Holiday Spectacular.