Communist Unification Party (in Spanish: Partido Comunista de Unificación) was a political party in Spain. Formed in 1976 through the unification of the two groups Lucha de Clases and Larga Marcha hacia la Revolución Socialista. Later the same year the Organización Comunista Información Obrera joined the PCU. PCU promoted abstention in the 1976 . In 1977 merged into the Party of Labour of Spain (PTE).