Greene was born in Ottawa, Ontario to Russian Jewish immigrants, Daniel and Dora Green. He was called "Chaim" by his mother, and his name is shown as "Hyman" on his school report cards. In his biography, the author, his daughter Linda Greene Bennett, stated that it was not known when he began using "Lorne", nor when he added an "e" to Green.
Greene began acting while attending Queen's University in Kingston, where he also acquired a knack for broadcasting with the Radio Workshop of the university's Drama Guild on the campus radio station CFRC. He gave up on a career in chemical engineering and, upon graduation, found a job as a radio broadcaster for the Canadian Broadcasting Corporation (CBC).
