 Fazlul Karim was born in Harbang, a village in Cox's Bazar district in the province of Bengal, to Golam Quader Shikdar, a village leader and Feroza Begum on 14 September 1905.He was the elder son in a family of seven daughters and three sons.Fazlul was educated at the Harbang Union School and later moved to Government Muslim High School in Chittagong, from where he completed his matriculation.