Joe Keller is the patriarch of the family, he is a self-made man, who worked his way up from worker to boss/owner. He owns a factory that made airplane parts for the military during World War II. He is a decent man, a family man, a hard worker. Mostly Joe would be considered a real example of the average American, but he made a tragic mistake and then blamed it on someone else.
Joe's behavior regarding the shipment of the faulty airplane parts and then fingering his employee, Steve Deever as the culprit responsible for the criminal act which resulted in the deaths of several pilots flying planes withe the faulty parts. Joe got out of jail by lying about his role in the shipping of the airplane parts.
Joe is a contradition, on the one hand he is honest, patriotic, loves his family, on the other hand, he is dishonest, manipulative and selfish, unwilling to risk losing his business to behave in a moral way. If he had not shipped the airplane parts, his business would have gone under, but he would have been a honorable family man. He puts his business, which he claims is all for his family, ahead of his own integrity, dignity and honesty.
Kate Keller, Joe's wife, the mother of Larry and Chris. Kate suffers from a delusion a belief that Larry, who has been missing in action, is still alive. His room is kept as a shrine, his clothes are ready to be worn, his shoes are shined. Kate won't accept that Larry is dead. She is abrasive towards her husband, during the early part of the play, she does not reveal that she knows that Joe is guilty. Kate has more sense than Joe, she accepts the end result of Joe's decision. Kate turns out to be more realistic than first thought.
Larry is missing in action and is never heard or seen in the play. He is the son of Joe and Kate and brother to Chris. Larry was engaged to Anne Deever, the daughter of Steve, the man that Joe blamed for the shipping of the faulty airplane parts to the military. Larry is regarded as a hero, a tree is planted in the yard as a memorial to him. Actually, Larry has committed suicide, and only Ann knows why. She reveals all to the family, when Joe finds out that Larry killed himself because of what he did with the faulty airplane parts, he goes in the house and shoots himself dead.
Chris Keller is an idealist, a veteran of WWII who came home alive, Chris is guilty that his brother is missing and he is alive. He believes that his father is an honest man, never doubting that Steve was the one who shipped the faulty parts. Chris has summoned Anne Deever, Larry's girl, as Kate calls her, because he is in love with her, he has proposed marriage to her. But Chris is unable to accept the truth about his father, and cannot bear to face Anne, he sends her away.
Jim is a neighbor who is a doctor, he is married to Sue, who despises Chris Keller for intruding on her life trying to get Jim to give up his medical practice and go into research. Sue resents Chris for suggesting this because research pays a lot less than the medical practice.
Frank is another neighbor who prepares Larry's horoscope to support Kate Keller's belief that her son is still alive.
Bert is the little boy in the neighborhood that Joe Keller plays policeman and jail with, which irritates Kate Keller so much, she feels that he should not play such a game since he was in jail. Bert really looks up to Joe as a hero.