One of the central themes in The Things They Carried is the nature of storytelling itself. Many of the stories in the collection have metafictional qualities, and the narrator often draws attention to the blend of fact and fancy which goes into telling a story. Even a story based on fact is not entirely the hard, unvarnished truth, as O'Brien points out over and over.

Stories are also changed depending on the desires of the author. In "Love," which largely takes place years after the war, Tim meets First Lieutenant Jimmy Cross again and tells him he is writing about his experiences in Vietnam. Jimmy tells him to make him out to be a better person than he actually was and not to bring up anything that might show him in an unflattering or vulnerable light:

[Jimmy] got into his car and rolled down the window. "Make me out to be a good guy, okay? Brave and handsome, all that stuff. Best platoon leader ever." He hesitated for a second. "And do me a favor. Don't mention anything about—."
"No," I said. "I won't."

"How to Tell a True War Story" is one of the most metafictional stories in the book. The narrator says outright that "true war stories" are never about imparting morals or instructing the reader. He also says "it's difficult to separate what happened from what seemed to happen," since subjectivity plays such a big part of memory. So, even though none of the stories are exact reproductions of reality, they are authentic reproductions of the subjective experience of being in the Vietnam War.