Young spent the first seven years of his life in Scotland. His siblings were Stephen Crawford (1933–1989), Margaret (1935–2019), John (born 1938), Alexander (1938–1997), William (born 1940), George (1946–2017) and Malcolm (1953–2017). Music was part of family life.

Young onset dementia usually progresses more quickly than types of dementia first seen after 65. For instance, Malcom Young is said to have had dementia for only three years. However, at the time of diagnosis, the person and their family often can look back and recognize early signs began some years ago.

Young is the son of Stephen Crawford Young Sr. (1933–1989), who was the eldest brother of Angus, Malcolm, George, and Alex Young. He emigrated with his family from Scotland to Sydney in 1963.

Angus Young was born on March 31, 1955 in Glasgow, Scotland. At school, Angus was an unenthusiastic student. His only real academic interest was art which allowed him some freedom of expression. He gave up school at 15 and went to work for a soft porn magazine called Ribald as a printer.