Bernie Grant was born on 17th February 1944 in Georgetown, Guyana into a family of teachers. His father, Eric, was a headmaster and, later, principal of a Teachers' Training College. His mother, Lily, was a highly respected teacher, both in Guyana and in Haringey, North London and several of his close relatives also chose education as their profession, including his uncle, Basil Blair, who was a President of the Guyana Trades Union Congress.

Bernie was the second child and second son of five children and spent three years at his father's primary school in Ituni, one of the bauxite-mining districts of Guyana. During this time Bernie was introduced to Amerindian culture and ideas an experience which was to have an enormous impact on how he viewed the world. He returned to Georgetown at the age of nine to attend Sacred Heart Roman Catholic School, from where he won a scholarship to St Stanislaus College, a Jesuit boys' secondary school.

The Charlestown area of Georgetown in which he grew up, was diverse with rich and poor families of different races. Bernie was very popular, since he was sociable and good at sports, especially cricket and basketball.

Although he passed his O Levels with flying colours, Bernie left school a year later because he wasn't allowed to study his preferred subjects. He then worked for two years as a laboratory analyst before he left for England to join his family.