La ciénaga ([la ˈsjenaɣa] English: The Swamp) is a 2001 comedy-drama film written and directed by Lucrecia Martel in her feature directorial debut. The film stars an ensemble cast featuring Graciela Borges, Mercedes Morán, Martín Adjemián and Daniel Valenzuela.

The film is set in the high plains of northwestern Argentina and portrays the life of a self-pitying Argentine bourgeois family. It has received critical acclaim.

In 2022, it was selected as the greatest film of Argentine cinema in a poll organized by the specialized magazines La vida útil, Taipei and La tierra quema, which was presented at the Mar del Plata International Film Festival. Also in 2022, the film was included in Spanish magazine Fotogramas's list of the 20 best Argentine films of all time.