Jim Carroll is the narrator of The Basketball Diaries. He is 13 years old when the entries begin in 1963 and 16 when they end in 1966. Jim spends the first half of his youth in the lower east side of New York City and is shaped by the culture there. Ignored and disliked by his family, Jim spends most of his time on the streets with his friends, earning money for drugs or using them. Even when Jim is offered a scholarship to a privileged Catholic school, he cannot avoid drug culture. Instead, he regularly visits his friends to do drugs and play basketball—none of whom are particularly significant and serve more as catalysts for certain events. Jim does not get attached to people or his surroundings because he views his existence as fleeting. War is all around him and seems to be never-ending, leaving him to believe he will not live long.

Jim has two hobbies outside of his street life: basketball and writing. Basketball is Jim’s escape from the chaos of the streets and political climate. He plays with people of all creeds and races despite racism being heavily accepted at the time.