Reviews for the novel have been generally positive. Gilbert Cruz of Entertainment Weekly gave the novel an "A" rating, commenting that the novel shared with great zombie stories the use of a central metaphor, describing it as "an addictively readable oral history." Steven H. Silver identified Brooks' international focus as the novel's greatest strength and commented favorably on Brooks' ability to create an appreciation for the work needed to combat a global zombie outbreak. Silver's only complaint was with "Good-Byes"—the final chapter—in which characters get a chance to give a final closing statement. Silver felt that it was not always apparent who the sundry, undifferentiated characters were. The Eagle described the book as being "unlike any other zombie tale" as it is "sufficiently terrifying for most readers, and not always in a blood-and-guts way, either." Keith Phipps of The A.V. Club stated that the format of the novel makes it difficult for it to develop momentum, but found the novel's individual episodes gripping. Patrick Daily of the Chicago Reader said the novel transcends the "silliness" of The Zombie Survival Guide by "touching on deeper, more somber aspects of the human condition." In his review for Time Out Chicago, Pete Coco declared that "[b]ending horror to the form of alternative history would have been novel in and of itself. Doing so in the mode of Studs Terkel might constitute brilliance."
Ron Currie Jr. named World War Z one of his favorite apocalyptic novels and praised Brooks for illustrating "the tacit agreement between writer and reader that is essential to the success of stories about the end of the world ... [both] agree to pretend that this is not fiction, that in fact the horrific tales of a war between humans and zombies are based in reality." Drew Taylor of the Fairfield County Weekly credited World War Z with making zombies more popular in mainstream society.
The hardcover version of World War Z spent four weeks on the New York Times Best Seller list, peaking at number nine. By November 2011, according to Publishers Weekly, World War Z had sold one million copies in all formats.