Jaden Yuki is a student at the Duel Academy, the most prestigious duel training school, and his skills and intuition are unmatched. Jaden is noticed by Yugi Muto, the great duelist, who senses that Jaden's destiny holds a lot of potential. The numerous Yu-Gi-Oh GX characters keep the 'Yu-Gi-Oh' cartoon series dynamic and engaging with each episode.

The principal cast is composed of series hero Jaden Yuki, the passionate Alexis Rhodes and her brother Atticus, the easily discouraged but determined Syrus Truesdale, elitist Chazz Princeton, the analytic Bastion Misawa, the strong-willed Tyranno Hassleberry, and the love-struck Blair Flannigan.

Supporting characters often have connections to the educative or professional dueling worlds, and include Obelisk Blue professor Vellian Crowler, duelist-turned-Industrial Illusions designer Chumley Huffington, and Pro League powerhouses Zane Truesdale and Aster Phoenix. The Overseas Champions, a group of foreign duelists introduced in the third year, would also find a place in Duel Academy's student body.

Villains of the series range from elderly Kagemaru to the manipulative Sartorius and the deranged Yuber.

Jaden Yuki - although he doesn't get the best grades at the Duel Academy, Jaden Yuki has a special connection with the monsters and a series of dueling skills that are unmatched by any of the other students. Jaden's future is uncertain but there is huge potential and the world might soon realize that Jaden is the greatest duelist of all times.

Alexis Rhodes - one of the other main characters of Yu-Gi-Oh GX is Alexis Rhodes, considered the Queen of Obelisk Blue. Alexis admires Jaden but is, at the same time, sad about the disappearance of her brother.

Zane Truesdale - as part of Obelisk Blue, Zane is undefeated in combat. His elite dueling skills are impressive, but Zane Truesdale still has a lot to learn about human nature, as he constantly disregards the abilities of his younger brother, Syrus.

Chazz Princeton - talented and cunning, Chazz believes that those with low academic grades have no place among the elite duelers - Jaden is first on his list.

Chumley Huffington - he would be a formidable opponent if his laziness wouldn't always get in the way.

Syrus - his academic performance is even lower than Jaden's, mainly because he lacks the confidence and is always in the shadow of Zane, his older brother.

Bastion Misawa - he wins battles by analyzing each move with precision and intuition. Bastion Misawa is one of the students with the highest grades in the Duel Academy.

Dr. Crowler - while Dr. Vellian Crowler is a teacher at the academy, he only devotes his energy for the elite learners and tries to push slow learners aside.

Professor Banner - always accompanied by his cat friend, Pharaoh, Professor banner is head of the Slifer Red Dorm.