The Workers and Peasants' Bloc (in Catalan: Bloc Obrer i Camperol, in Spanish: Bloque Obrero y Campesino) was a "Right Opposition" communist group in Spain. BOC was founded in Barcelona in 1931, as the mass front of the Catalan-Balearic Communist Federation (FCCB), after the merger of the Catalan Communist Party into FCCB. FCCB, which made up the nucleus of BOC, later changed its name to Iberian Communist Federation, thus stating its intention to expand itself and BOC throughout Spain.
The central publication of BOC was La Batalla. BOC also published L'Hora and El Front in Barcelona, L'Espurna in Girona and Avant in Lleida.