The protagonist of the novel, "O'Brien" symbolizes memory and storytelling, two central themes of the novel. He is a young foot soldier in the Vietnam War, a member of Alpha Company. He is also the fictional persona of O'Brien the writer, and similarly is a middle-aged writer with a Midwestern, middle-class background that informs his values. Readers follow "O'Brien" around Vietnam, experiencing his fear, guilt, curiosity, and blood lust. For all of the first hand accounts and stories, "O'Brien" is the readers' source, and he demonstrates the danger of believing that something is either fact or fiction, often by evoking emotions in the reader.
Kiowa Kiowa symbolizes the wastefulness of war. He is a foot soldier in Alpha Company, a Native American Baptist who always keeps an illustrated New Testament with him. He is O'Brien's closest friend in Vietnam and is killed in battle when he drowns in a field during a flood. When "O'Brien" returns to Vietnam, he visits the site of Kiowa's death and leaves his moccasins as a memorial to his friend.
Curt Lemon Lemon represents an outdated model of masculine heroism. He is brave and fearless to a fault, known in Alpha Company for pulling crazy stunts just for the attention and the thrill of danger. He even makes a dentist pull a healthy tooth from his mouth to prove to everyone that he is not afraid of dentists. Eventually stepping on a booby trap kills him.
Lt. Jimmy Cross The leader of Alpha Company, Cross personifies mental escapism, the ability to project one's mind somewhere else to escape from an undesirable situation. Instead of concentrating on the war, Cross occupies his mind with memories of Martha, his old sweetheart. Rather than helping to search for Kiowa's body, Cross spends time thinking about the letter he must write to Kiowa's father. Cross meets up with O'Brien after the war, and he still carries feelings of unrequited love for Martha. Whether in the middle of the war or 20 years later, Cross focuses on life outside of war, but also carries a heavy, self-imposed burden of guilt because of it.
Norman Bowker A foot soldier in Alpha Company, Bowker embodies the effect known as "survivor guilt." He cannot forgive himself for outliving his friends who died in battle. He feels intense culpability for Kiowa's death and cannot adjust to civilian life in his small hometown after the war. He wants O'Brien to write a story about a guy like him who cannot talk about his war-related trauma. Bowker eventually commits suicide.
Rat Kiley The medic of Alpha Company, Rat represents the allure and the danger of storytelling. He is known for spinning yarns and making grotesque exaggerations. Rat helps O'Brien when he is shot for the first time. Rat's imagination eventually claims his sanity, as he begins to hallucinate in-country. He shoots himself, not to kill, but to be excused from war because of injury.
Azar A foot soldier in Alpha Company, Azar is the wild man who enjoys war. He makes jokes about death, even the death of Kiowa. He mocks the movements of a traumatized Vietnamese girl dancing for fun and helps O'Brien play a cruel prank on Jorgenson. Azar's real allegiance is to war itself, not to his friends or his cause.
Henry Dobbins Dobbins is a foot soldier in Alpha Company who symbolizes "America itself, big and strong…slow of foot but always plodding along." He is a large man with a soft heart who feels sympathy for others and anger against unwarranted cruelty. He has a keen sense of morality and treats everyone, enemies and friends, with respect.
Mitchell Sanders The radio officer of Alpha Company, Sanders is the voice of soldierly experience and practical wisdom. He tells stories about how other soldiers react to Vietnam, and he vehemently blames Lt. Cross for Kiowa's death due to his incompetence as a leader.
Ted Lavender A soldier in Alpha Company who represents emotional escapism from the war. He achieves this escapism through drug abuse and ultimately is killed.
Dave Jenson and Lee Strunk These Alpha Company soldiers demonstrate the close relationship between aggression and camaraderie. They serve as foil for one another, each bringing the other to the edge of loyalty and violence. They make an agreement to kill the other should he sustain a permanently debilitating wound.
Bobby Jorgenson The medic who replaces Rat Kiley, Jorgenson symbolizes the young, inexperienced, "green" soldier, or "FNG." When O'Brien is shot a second time, Jorgenson is too afraid to help him quickly, and O'Brien subsequently develops a hideous infection. O'Brien later gets revenge when he and Azar play mind tricks on Jorgenson.
Young soldier in the field Representing naiveté and shock, this member of Alpha Company is talking to Kiowa when the attack begins that takes Kiowa's life. The next morning he cannot think of anything but the picture of his girlfriend lost in the attack.
Mary Anne Bell Girlfriend to soldier Mark Fossie, she represents the corruption of innocence that takes place in war. She arrives wearing "white culottes and this sexy pink sweater," fresh from suburban U.S., and becomes a bestial instrument of death, scarier than even the Green Berets.
Mark Fossie Medic at Tra Bong who brings his girlfriend, Mary Anne Bell, over to Vietnam from the U.S.
Eddie Diamond Narcotic-addicted, highest-ranking officer in the Tra Bong area medic camp that Rat Kiley is temporarily assigned to with Mark Fossie and Mary Anne Bell.
North Vietnamese soldier Soldier killed by "O'Brien." "O'Brien" invents an entire personal history for this soldier and feels shock and guilt for killing him. The soldier also appears in "O'Brien's" dreams years later.
Vietnamese girl Traumatized sole survivor of a village, Alpha Company comes across this girl dancing in the midst of rubble and corpses.
Kathleen Young daughter of "O'Brien" who accompanies him back to Vietnam and to the spot where Kiowa died. She cannot understand why her father cannot put the war behind him.
Linda Fourth-grade girlfriend of "O'Brien." They saw a war movie on a date. She died from a brain tumor. Hers was the first dead body "O'Brien" saw.
Timmy Fourth-grade persona of "Tim O'Brien" who felt a "deep and rich…love" for Linda.
Nick Veenhof Fourth-grade classmate of "O'Brien" and Linda who, being a prankster, pulls Linda's hat off, revealing her bald head and surgery scars.
Lemon's sister Curt Lemon's sister, who did not respond to Kiley's letter about her brother's death because, presumably, she found the letter's content disturbing and inappropriate.
Martha Lt. Cross's love interest; he keeps her picture with him in Vietnam. She does not return his feelings. "O'Brien" suggests that she has a secret, possibly that she had been raped. She becomes a Lutheran missionary and does not want to be married.