Bulma in Dragon Ball GT is a brilliant scientist and the heiress to the Capsule Corporation, having inherited the company from her father, Dr. Brief. As the series begins, she is in her late fifties or early sixties, though she maintains a youthful appearance and vibrant energy. Her role in the story is largely technical and strategic, as she no longer participates in direct combat but remains essential to the Z Fighters' efforts through her inventions and intellect.

Throughout Dragon Ball GT, Bulma's personality retains the core traits that have defined her since her youth. She is exceptionally intelligent, temperamental, and vain, often displaying a spoiled yet confident demeanor. Her vanity and lack of a pure heart, a running gag since the original Dragon Ball, continue to prevent her from riding the Flying Nimbus. Despite her occasional selfishness, she is deeply loyal to her family and friends, consistently using her scientific expertise to help them face new threats. She approaches problems rationally and is highly persistent, often making critical decisions when the situation demands action.

One of the most significant events for Bulma in Dragon Ball GT occurs during the Baby Saga. The parasitic alien Baby, seeking revenge against the Saiyans, takes control of the Earth's population. Bulma is among those possessed by Baby, becoming one of his key subordinates. In this state, her genius is turned toward villainous purposes; she organizes the migration of Earth's population to a new Planet Tuffle and creates the Super Bruits Wave Generator, a device that amplifies Blutz Waves to help Baby-Vegeta achieve the Golden Great Ape transformation. This storyline demonstrates how formidable Bulma could be if her intellect were ever used for evil purposes, as she becomes a terrifying and efficient lieutenant for the arc's main antagonist. She is eventually freed from Baby's control when the sacred water from Dende's Lookout is used to purge the parasite from Earth's population.

Later in the series, Bulma plays a crucial role in the battle against the Shadow Dragons. After the evil dragon Omega Shenron proves too powerful for even Super Saiyan 4 Goku, Bulma creates a new Blutz Wave Generator. This device exposes Vegeta to the necessary waves, allowing him to transform into a Super Saiyan 4 for the first time, enabling the two Saiyan rivals to fight together. Her technological prowess once again proves to be a decisive factor in a battle that pure strength alone could not win.

Bulma's key relationships continue to evolve in Dragon Ball GT. Her friendship with Goku, which began when they first met as teenagers, remains a central pillar of the series. She is one of the few people who has known him since childhood and continues to support him unconditionally. Her marriage to Vegeta is shown to be a stable, if still quarrelsome, partnership. While they bicker, their mutual respect and affection are evident, and she takes pride in both her Saiyan prince husband and their children, the adult Trunks and the teenage Bulla (also known as Bra). Her role as the matriarch of the Briefs family is firmly established, and she presides over the Capsule Corporation with authority.

Unlike the action-oriented fighters, Bulma's abilities lie entirely in her scientific genius. She is responsible for constructing the spacecraft that Goku, Trunks, and Pan use to travel across the universe in search of the Black Star Dragon Balls. Her understanding of advanced physics, engineering, and alien technology, much of which she developed over decades of studying Saiyan and Namekian ships, makes her indispensable. While she has no notable combat skills or ki manipulation, her inventions—from the Dragon Radar to the Blutz Wave Generator—are consistently the key to overcoming the series' seemingly insurmountable obstacles.