"Air Gear" is set in a world where advanced inline skates known as Air Trecks (A-T) have revolutionized personal mobility and spawned a competitive subculture of street battles. The story centers on Itsuki Minami, a high school delinquent with a natural talent for A-T. Living with the Noyamano sisters—Ringo, Mikan, Ume, and Kakei—Itsuki discovers that they are part of a legendary A-T team called Sleeping Forest. After finding a pair of high-performance A-T called Storm Regalia, Itsuki becomes deeply involved in the underground world of A-T battles, where teams, known as "Ride," compete for dominance and territory.

As Itsuki forms his own team, Kogarasumaru, he encounters various rival Rides, each with unique skills and philosophies. The narrative explores the dynamics of teamwork, rivalry, and personal growth as Itsuki and his teammates face increasingly formidable opponents. Key characters include Ringo Noyamano, who serves as a mentor and love interest; Kazu, a loyal friend and skilled rider; and Simca, a mysterious and powerful A-T rider with ties to the enigmatic Sky Regalia. The story delves into the origins of A-T technology, revealing its connection to a secretive organization known as Genesis, which seeks to control the future of A-T and its users.

Themes of ambition, identity, and the pursuit of freedom are woven throughout the series, as Itsuki strives to become the "Sky King," a title representing the pinnacle of A-T mastery. The plot intertwines intense action sequences with moments of character development, exploring the personal struggles and motivations of both protagonists and antagonists. The series balances its focus on high-stakes battles with a deeper exploration of the bonds formed through shared goals and challenges, culminating in a climactic struggle for the future of the A-T world.