The All India Forward Bloc (abbr. AIFB) is a left-wing nationalist political party in India. It emerged as a faction within the Indian National Congress in 1939, led by Subhas Chandra Bose, and was strongest in West Bengal. The party re-established as an independent political party after the independence of India. During the 1951–1952 and 1957 Indian general election, the party was known as Forward Bloc (Marxist). The party's current Secretary-General is G. Devarajan. Veteran Indian politicians Sarat Chandra Bose (brother of Subhas Chandra Bose) and Chitta Basu had been the stalwarts of the party in independent India.
Leveraging Netaji's sway over the populace, the organization had established its electoral footprint after Independence in states like Tamil Nadu, Andhra Pradesh, Kerala, and Assam, with West Bengal as its primary bastion. However, after eight decades, the party, now confined to select regions, lacks any Members of Parliament or Legislative Assembly representatives.