Gohan is the first son of Goku and Chi-Chi, making him a hybrid of Saiyan and human lineage. By the time of Dragon Ball GT, Gohan has matured into a full-fledged adult, having left his childhood and teenage fighting days behind. He is married to Videl, and together they have a daughter named Pan, who becomes a central character in the series. Gohan works as a researcher for Capsule Corporation, the company founded by Bulma's family, a role that reflects his lifelong dedication to intellectual pursuits over combat.

In his adult life, Gohan has fully embraced a scholarly and domestic lifestyle. His personality is gentle, reserved, and focused on his family responsibilities. Having never shared his father Goku's pure love for battle, he has almost entirely given up formal training. Instead, he channels his intelligence into his research work and prioritizes being a good husband to Videl and a protective father to Pan. This shift in priorities represents the culmination of his mother Chi-Chi's early wishes for him to become an academic success. He is often seen dressed in formal business attire, including a suit and tie, and wears eyeglasses, a stark contrast to the martial arts gi of his youth.

Despite his peaceful life, Gohan's role in the story is reactivated when the Earth faces existential threats. Early in Dragon Ball GT, he uses his scientific knowledge to assist Bulma in constructing the spaceship that will carry Goku, Trunks, and later Pan on their mission to collect the Black Star Dragon Balls. Although he no longer trains regularly, his latent power remains formidable. He is still one of the strongest warriors on Earth, though his power has diminished from the heights he achieved during the battle against Majin Buu.

Gohan maintains several key relationships that define his character. His bond with his mentor Piccolo remains profoundly deep. The Namekian, who once trained a young Gohan to be a warrior, continues to watch over him. Their connection reaches a tragic climax when Piccolo chooses to remain on Earth as it explodes, ensuring the Black Star Dragon Balls are destroyed permanently. In a telepathic farewell, Piccolo expresses his pride in Gohan's growth and maturity, leaving Gohan devastated by the loss. His relationship with his father Goku is also present, though Goku has been turned into a child and is often away in space. Gohan interacts with his brother Goten, though Goten, like Gohan, has also grown up and become more concerned with his personal life than with fighting. He is protective of his daughter Pan, which drives him to intervene in dangerous situations.

The character undergoes notable development across the series, though many fans and even the series scriptwriter felt his arc was not fully realized. Initially, he is a pacifist scholar who has abandoned fighting. However, when his family is threatened, he is forced to return to battle, though he is often unable to match the immense power of the series' main antagonists like Baby and Super 17. The scriptwriter for Dragon Ball GT, Atsushi Maekawa, has stated he wanted to dedicate more episodes to a dramatic resolution for Gohan, where he would rediscover his fighting spirit after seeing his loved ones harmed, but time and production constraints prevented this from being fully fleshed out.

In terms of notable abilities, Gohan is still capable of accessing the Super Saiyan transformations, though his power is significantly reduced compared to his peak in Dragon Ball Z. He no longer possesses access to his "Mystic" or "Ultimate" form, which previously allowed him to fight without transforming. As a result, he is forced to rely on the standard Super Saiyan and Super Saiyan 2 states in battle. He is able to use iconic techniques such as the Kamehameha wave and the Masenko, a technique taught to him by Piccolo. Despite his diminished power, he can still hold his own against powerful foes like General Rilldo and was one of the fighters who helped restore energy to Goku during his battle against Baby. In the final confrontation with Omega Shenron, Gohan briefly sets aside his scholarly attire to wear an orange martial arts gi similar to the one his father wore in his youth, signifying a brief return to his warrior heritage.