The research presented in this thesis deals with the first extensive narrative work in Spanish literature, that is, the Cantar de Mio Cid (XII - XIII centuries). The research interest focuses on the jokes and humorous language found in the work. The study focuses on an in-depth analysis of these same elements, to date largely unexplored, or generally carried out superficially. This may be a result of the controversy that concerns their true presence in the Cantar. However, the thesis and arguments presented herein argue the validity of the methodological approach; that is, regardless of the conscious or unconscious inclusion of these elements in the Cantar, the fact remains that they exist in the text and are closely related to burlesque humour. Those jokes and humorous language have a clear proselytizing and warlike function and intent, and include the subtle fostering of a certain hatred and anti-Semitism latent in the period. The arguments and analysis presented in the course of this work are corroborated by the results of a textual, historical, and sociocultural interpretation of the Cantar de Mio Cid, as well as the theory of jokes, according to Sigmund Freud.