My Best Enemy (Spanish: Mi mejor enemigo) is a 2005 Chilean/Argentine/Spanish drama directed by Álex Bowen. It stars Nicolás Saavedra, Erto Pantoja and Felipe Braun and won the Pudú de Plata for the best Chilean movie at the Valdivia International Film Festival.

My Best Enemy tells the story of a 5-man Chilean patrol lost in Patagonia during the Beagle conflict of December 1978. The patrol becomes lost and builds a trench in the middle of the Patagonian plains only to discover that there is an Argentine trench in front of them. Likewise the Argentine group is also lost and unsure of the actual location of the country's border. The story is set during a period in which war seems imminent, and portrays these two groups interacting in ways both friendly and conflictive (hence the title of the movie).