Jess is a ten-year-old middle child and the only boy in a struggling, working-class family of seven in rural Virginia. He secretly harbors a passion for drawing but hides his artwork out of fear of ridicule from his practical father and his classmates. Burdened by daily farm chores and a lack of parental attention, he seeks validation through running until a new friendship offers him a completely different way to build confidence.

Leslie is an intelligent, confident tomboy who recently moved to the rural town of Lark Creek from a wealthy suburb. Unlike her peers, she lives without a television and dresses practically, making her an immediate target for gossip at school. Her vivid imagination and disregard for traditional gender expectations make her a natural leader as she helps create the imaginary country of Terabithia in the woods.

May Belle is Jess's seven-year-old sister and the sibling who looks up to him the most. She is innocent, somewhat gullible, and deeply entrenched in the strict religious beliefs of her community. Though Jess sometimes treats her dismissively out of his own frustration, she remains fiercely loyal to him.

Miss Edmunds is the traveling music teacher who visits the underfunded school once a week. She stands out in the conservative town due to her informal teaching style, guitar playing, and casual dress code, which earns her the label of a "hippie" among locals. She is the only adult who validates Jess's artistic abilities.

Jess's father is a physically exhausted laborer who commutes daily to Washington, DC. The heavy financial burden of providing for a family of seven leaves him with little energy or emotional capacity for his middle son. He holds rigid expectations regarding masculinity, which creates a barrier between him and Jess's artistic interests.

Mrs. Aarons is the stressed, middle-aged matriarch of the family. The continuous pressure of poverty and raising five children makes her irritable and quick to scold. She relies heavily on Jess for farm chores while frequently allowing her older daughters to manipulate their way out of work.

Bill and Judy are affluent, highly educated writers who relocated to the country to reassess their values and pursue a simpler life. They lack practical farming or renovation skills but approach their rural experiment with enthusiasm. Unlike many parents in the community, they treat children as intellectual equals and hold progressive views.

Mrs. Myers is the imposing fifth-grade teacher at Lark Creek Elementary, known by the students as "Monster-Mouth Myers." She runs a strict classroom to manage the severe overcrowding and lack of resources, though she quickly takes a liking to the highly articulate new student in the front row.

Brenda and Ellie are Jess's two oldest sisters. They are highly focused on fashion, social status, and avoiding household labor at all costs. They frequently mock Jess for his physical appearance after running and view his friendship with a tomboy as highly irregular.

Joyce Ann is the four-year-old baby of the Aarons family. She uses her position as the youngest to her advantage, crying loudly at any provocation to ensure her mother intervenes on her behalf.

Janice Avery is an intimidating seventh-grader who terrorizes the younger children at Lark Creek Elementary. She uses her size and aggressive demeanor to demand lunch money and treats, though her tough exterior masks difficulties in her own home life.

Gary is a fifth-grade classmate of Jess who considers himself the fastest runner in the grade. He is aggressive in maintaining his social standing among the boys and strongly objects when a girl attempts to join their recess races.

Prince Terrien is a stray puppy that joins the neighborhood around the holidays. He is energetic, constantly in motion, and serves as the official, albeit easily distracted, guardian of the imaginary kingdom in the woods.

Miss Bessie is the Aarons family's dairy cow. Milking her is one of Jess's primary daily chores. She provides a quiet, reliable presence during his early morning routines and moments of stress.