A jokester even more hyper than Tobias who loves cracking jokes, though they aren't very funny. He is in the soccer club and is one of Gumball's top five friends.

A wealthy show-off who acts high and mighty. He is in the soccer club and has an older sister named Rachel. He is not popular with girls at all. He is Gumball's sixth-best friend, and upon learning this, he tried to become the number one best friend.

The protagonist of the series. While selfish and foul-mouthed, he actually has a strong sense of justice and a kind heart. He isn't very bright. He is allergic to makeup and hates spiders. He is also notoriously unphotogenic. While he claims to have no special talents, he possesses many superhuman abilities. His best friend is Darwin, and he has a crush on Penny.

The deuteragonist of the series. He has a happy-go-lucky and innocent personality. He is Gumball's former pet, best friend, and brother. Although he is two years younger than Gumball, they attend the same school. He is allergic to feathers and his favorite food is potatoes.

Gumball's younger sister. She is fearful and shy but has a sharp tongue and is incredibly intelligent. As an infant, she was quite a dangerous baby, often pranking or even attempting to kill her brother. She is in the 8th grade (equivalent to the second year of middle school in Japan), one grade above Gumball, and ranks first in the country. Her birth tag said 'Anias,' but she corrected it to 'Anais' herself, showing her extreme intelligence.

A male character who uses feminine pronouns (I - soft/feminine). He is in the synchronized swimming club. He is very feminine and often hangs out with the girls. He has been dancing since birth and is skilled with musical instruments.

To put it simply, he is a ridiculously good guy. He is so nice that he often says overly cheesy lines. He is the polar opposite of Gumball in that he is extremely photogenic.

A character who tends to take things a bit too far. He can use the Konami Code. He is dangerous because you never know what he'll do when he gets angry.

A high-performance robot. He is a member of the Outcasts Club. He can transform into a 'Battle Mode.' He lacks emotions. He once tried to steal Gumball's life.

A calm and kind-hearted character. She is a yellow shapeshifter. She has a pet spider named Cuddles.