The main character and protagonist of the novel. Jess is a fifth-grader living in a rural Southern area. He is lonely and lost in the middle of a family of four girls when Leslie Burke moves in next door. Leslie and Jess become best friends, and the novel centers on their friendship. Jess is a budding artist whose talent receives little praise from anyone except Leslie and Miss Edmunds. Yet he is quite talented, as well as intelligent, caring, and down- to-earth. A thoroughly likable character, we are quickly drawn into his world and his personal tribulations.
Jess's new next-door neighbor and best friend. Highly intelligent and imaginative, it is her idea to build a fantasyland named Terabithia across the creek. Leslie's family is affluent and well educated, in stark contrast with the rest of the residents in the area, and has an entirely different slant on life than any of the neighbors. All this influences Leslie as well and helps to develop her uniqueness and distinct flair.
Jess's mother. Mrs. Aarons is tired and careworn with the stresses of trying to support a family of seven on a poor family's income. She always seems to be hounding Jess to do chores or milk the cow, but her shortness of temper is merely a result of overwork. After Leslie's death, she shows herself to be a caring mother torn apart by her son's pain. Nevertheless, under normal circumstances she does not help to make Jess's home life inviting or comfortable.
Jess's father. Mr. Aarons is likewise harried by the concerns of being the sole breadwinner for a large family. He rarely has time for Jess, which is hard on the boy. He wants to do the right thing by his son, but he isn't quite sure how; the irony is that all he would really need to do would be to sit down with Jess, ruffle his hair, and talk with him about his day, but he doesn't seem to understand this. He expects Jess to be a "man," a source of considerable heartache and soul-searching on the part of Jess, whose passions lie elsewhere than playing football and driving big trucks. However, he is concerned with his son's welfare and wants nothing but the best for him, as is evidenced in his treatment of Jess after Leslie's death.
Jess's oldest sister. Her age is never given directly, but we can guess that she's about fifteen or sixteen. Ellie is thoroughly spoiled, much like Brenda, the difference between them is that Ellie has mastered the art of sycophancy, and consequently leaves a much better taste in most people's mouths. Vain, conceited, and shallow, Ellie continually annoys Jess.
Jess's second-oldest sister. We can surmise that she is around fourteen. Brenda is even more annoying than Ellie. She shares Ellie's vanity and shallowness, but she whines continually and has no sense of when to stop before pushing people too far. She harries Jess continually, and is primly content with her own little world of makeup, scanty clothing, and romantic interests. Even after Leslie's death, Brenda will not stop harassing Jess. She is wholly immature and self-absorbed.
Jess's little sister. May Belle is closer to him than any other member of their family. She is six and a bit lost, and she is without close friends or siblings close enough in age to play with. She often tries to push herself in with Jess and Leslie, which they do not like, but all the same Jess feels bad for her. At the end of the novel, it is she who allows Terabithia to live on, as she becomes its new queen.
Jess's youngest sister, at four years old. Joyce Ann is not developed very much as a character. She is often portrayed as whiny, but she is only four. Jess does not share the same bond with her that he does with May Belle, but he seems to feel a certain warmth toward her, as is evidenced by the end of the book, when he suggests that in time, Joyce Ann may join May Belle in Terabithia as a princess.
The music teacher at the school. Jess is deeply in puppy love with her. She seems a creature from another world to him, a beautiful woman with a beautiful look and a smile for all the students, but especially Jess. She encourages his artistic talent, one of the two people in the world, including Leslie, who does, and seems to care about him in a special way. She is somewhat of a hippie, which only deepens her allure for Jess, because it confirms her individuality and separation from the narrow world of Lark Creek. Kind and caring, it is no mystery why Jess adores her, as she seems to fill a void of affection and compassion that he does not get from his family.
Leslie's father. He is a political writer who is extremely gifted intellectually but rather scatterbrained. Leslie's growing friendship with Bill disturbs Jess until Leslie invites him to spend time with them as well.
Leslie's mother. Judy writes novels and seems to spend most of her time closed in her room with her typewriter going. Not that she neglects Leslie, but she just seems busier than Mr. Burke. All in all, Leslie's parents lavish on her the love and attention that is not demonstrated clearly in Jess's house.
A seventh-grader who is the school bully. Janice terrorizes May Belle, as well as the rest of the younger kids, until Jess and Leslie find a way of getting back at her. However, Janice is not an ultimate demon; she has her own problems that lend her an aspect of sympathy. Her father abuses her, and when her friends blab her secrets to the entire school, her tough-girl persona snaps. It is Leslie who comforts her, at Jess's urging, forming an unlikely friendship between them.