The main protagonist of the Yu-Gi-Oh! ZEXAL series, a energetic boy who aspires to become a Duel Monster Champion. He has a special key given to him by his traveling parents, which manages to unlock a door to another dimension, where he encounters Astral. He uses a Deck given to him by his father. He soon obtains the power of Zexal, which allows him to combine his soul with Astral's and utilize ZW's. He is the current duel champion of Heartland City.
A mysterious entity from another world who serves as the secondary protagonist of the series. Astral makes a list of his observations of Yuma and other human behaviors while offering his dueling wisdom to the him in order to obtain the 99 "Numbers" Cards which are actually fragments of his memories which got scattered when he entered Yuma's dimension. He normally resides in a special world within Yuma's Key, featuring a strange ship whose parts become unlocked as Astral collects more "Numbers" cards.
one of the main characters who was originally a championship duelist before he was disqualified for peeking at his opponents cards, eventually becoming a delinquent and taking the nickname "Shark". Shark is now close friends with Yuma and fights the Barian threat alongside him and Kite.
Yuma's childhood friend. She doesn't duel, but has a Duel Gazer to see Yuma duel in Augmented Reality Duels. She is also intelligent, and good with computers. She has developed a rivalry with Cathy for Yuma's affections.
Kite is the son of Dr. Faker, a "Numbers" Hunter, and one of the main characters who was collecting "Numbers" for his father in order to help his formerly sick brother, Hart. Kite now fights the oncoming Barian threat alongside Yuma and Shark.
Rio is the younger twin sister of Shark. As a part of Vetrix's plan to use Reginald as their assassin against Dr. Faker, he sent his son Quattro to duel her. She eventually regains consciousness after Shark saves her from one of Barian's mind control and enrolls into Yuma's school. She is afraid of cats.
Bronk is Yuma's friend and a skilled duelist, who is known to defeat Yuma about 20 times already. Despite his harsh behavior toward Yuma, it is obvious he regards him as a friend. He often rides around on a skateboard. He develops a crush of Shark's sister, Rio.
Caswell is the class president in Yuma's class. He tends to add "in the end" or "to summarize" to his statements, even when it is not necessarily a summary.
A wily kid who often notes that everything in the world has a flipside. He is one of Yuma's friend.
Known as Cat for short, Cathy is a shy girl who has a crush on Yuma but doesn't stand out too well in class. she is able to communicate with Cats.
Anna Kaboom / Anna Kozuki
A former classmate of Yuma and Tori who supposedly had a crush on Yuma, but later realized that the boy she actually liked was someone else with a similar name. She later appears in the WDC finals though is knocked out during the knockout phase while protecting Yuma.
Rei has a positive attitude and is a huge fan of Yuma. Rei almost always follows him around and does whatever he can for him. Although sometimes, Rei's efforts end up troubling Yuma more than actually helping.
Kari is Yuma's older sister and reporter works from home always on the lookout for a scoop. She is generally against Yuma dueling as she is often worried about his safety.
Haru is Yuma and Kari's grandmother, who has been looking after them with their parents on business trips. She is often kind but will occasionally get strict over certain matters.
Yuma and Kari's father. During a dangerous expedition, he encountered a being from the Astral World and was given the Emperor's Key, which he later gave to Yuma. According to V, he is currently in the Astral World somewhere, having been betrayed by Dr. Faker.
Yuma and Akari's mother, who often goes on travels with Kazuma.
He is Kite's younger brother and Dr. Faker's youngest son who can create paths to other realities. He has been using this ability to send trash collected from Heartland City to attack Astral World. After his father and Barian are defeated, Hart is healed, losing all his powers and returning to the way he was before Kite started hunting "Numbers".
Kite's robotic assistance and is tall with drills in fighting form. He could transform into a Motorcycle and a Glider.
He is an Mad Scientist who wants to conquer Earth and destroy Astral World and the messenger. He is father of Kite Tenjo and Hart Tenjo. He is interest in Hart's power, and is therefore overly protective of him. Faker is responsible for the mutation of Vetrix and the disappearance of Kazuma Tsukumo. He is also able to see Astral's aura through Heartland's cameras.
He is a minor antagonist who is in charge of relaying Dr. Faker's orders to Kite Tenjo. He is the current Mayor of Heartland City. During the World Duel Carnival finals, Heartland took on the role of MC and would keep the duels away from the eyes of the public in order to have the duelist duel to their fullest potential.