The Vietnam War has always been a popular subject matter for American narratives，yet it is controversial among readers because of the pleasures produced by the true-to-life portraitures in such works. No doubt，the representations of such events imply great ethical consequences. This article delves into the relations between the ethical meanings and fictional representations of the Vietnam War through a deep analysis of Tim O’Brien’s Things They Carried. By resorting to contemporary trauma theories，this article analyses the various postmodern narrative modes adopted by O’Brien to depict the great traumas produced by the Vietnam War onto the soldiers. This article tries to prove that，rather than narrating the true stories of the War，or recounting the painful traumatic experiences，O’Brien is actually trying to convey to the reader the great difficulties of writing about trauma，and thus demand the reader to listen to the great pains of the narrators and the ways in which they attempt to break away from the shadows of the War.