Jack Gladney is the protagonist and narrator of the novel. He is a professor of Hitler studies at a liberal arts college in middle America.
Babette is Jack's wife. They have four children from previous marriages. She has an affair with Willie Mink, aka Mr. Gray, in order to obtain Dylar.
Heinrich is the fourteen-year-old son of Jack and Janet Savory. He is precociously intellectual, prone to be contrary, and plays correspondence chess with an imprisoned mass murderer.
Dana Breedlove is Jack's first and fourth wife and the mother of Mary Alice and Steffie.
Denise is the eleven-year-old daughter of Babette and Bob Pardee. She suspects her mother is a drug addict and steals the bottle of Dylar to hide it.
Steffie is the nine-year-old daughter of Jack and Dana Breedlove.
Wilder is Babette's six-year-old son, and the youngest child in the family. Wilder is never quoted for dialogue in the novel (however, at one point, it is said that he asked for a glass of milk), and periodically Jack worries about the boy's slow linguistic development.
Mary Alice is the nineteen-year-old daughter of Dana Breedlove and Jack's first marriage.
Murray Jay Siskind is a colleague of Gladney's. He wants to create a field of study centered around Elvis Presley in the same way that Jack has created one around Hitler. He teaches a course on the cinema of car crashes, watches TV obsessively, and cheerfully theorizes about many subjects.
Orest Mercator is Heinrich's friend who trains to sit in a cage with vipers.
Vernon Dickey is Babette's father who visits the family in chapter 33 and gives Jack a gun.
Willie Mink is a compromised researcher who invents Dylar.
Winnie Richards is a scientist at the college where Jack works, to whom Jack goes for information about Dylar.