Lieutenant Tobias Wolff
Wolff recounts his time in the Vietnam War in memoir form. He devotes much of his attention to retroactively interpreting his experiences according to his present knowledge. In the book, this looks like a long series of comments about Wolff's disgust with the person he was during his time in the service, whether because of immaturity or compromise.
Canh Cho
Canh Cho is Wolff's dog while he's in Vietnam. He's a faithful little companion, but Wolff cannot take him home with him. After a painful goodbye, Wolff attends his farewell dinner hosted by the natives who later reveal to him that they killed and cooked his dog to prepare the meal.
Sergeant Benet
Benet is Wolff's comrade in crime in My Tho. He shares Wolff's disdain and sheer boredom over "the cause." He prefers to exploit his circumstances by any means necessary in order to assuage his boredom and inconvenience.
Hugh Pierce
Pierce meets Wolff during flight school. He's a skilled pilot and graduates quickly, arriving in Vietnam long before Wolff. Although he dies almost immediately, he leaves an enduring impression on Wolff who recalls how Pierce lived with abandon, having once remarked how much fun he was having before jumping from an airplane.
Stu Hoffman
Hoffman flies back home with Wolff. He lands in San Francisco to reunite with his father, but he learns that his dad has changed a great deal. Having embraced the culture of the city, Hoffman's father is now a full-fledge hippy, a consequence of which is his rejection of the war. He is not proud of his son's service and actually reports a kind of embarrassment and betrayal over the entire affair, even though he acknowledge's Hoffman didn't have a choice. Unable to face the terror of war without his father's support, Hoffman deserts.
Geoffrey Wolff
Geoffrey is Wolff's brother. They are not especially close brothers, but they did learn to rely upon one another in their father's irresponsibility. Both brothers made private decisions not to visit their father in jail after he was caught for fraud.
Wolff's Father
Alas, Wolff feels no real kinship to his father. Although he cannot rid himself of the desperate need for his father's approval, he rationally understands that his dad is not a good standard by which to measure himself. Wolff's father is serving time in prison while Wolff is in Vietnam. Upon his son's return, he attempts an awkward reconciliation, but there is no common ground between the two and no demonstrated desire to change on either party's side.