Taking theoretical categories from psychoanalysis, the philosophy of language and the theory of documentary film, this work analyzes the nature of the phenomenon known as "false documentary", locating the place that this type of films has within cinema and documentary theory, analyzing various examples of multiple themes and establishing a reflection on the political consequences of false documentary, when presented as a symptom of documentary cinema, of historical, scientific and journalistic discourse, as it opens the possibility of telling the truth while lying. .