This paper aims to reconstruct the particular concept of revolution contained in the statements of the Chilean Popular Unity. In this sense, it is argued that the concept of revolution, particularly in the Popular Unity, is the result of constant friction between the Chilean Socialist Party and the Communist Party since the creation of the Popular Front in 1956. Differences between both parties are expressed mainly on three issues: the dichotomy around the policy of alliances which should follow the conglomerate; The discussion of the influence of the Cuban revolution in revolutionary practices at national and continental levels; and the role of democracy in the development of revolution.