Keith Johnson studied with János Starker and Gary Hoffman at Indiana University at Bloomington, graduating with a Bachelor of Music in 1980. Before joining the Melbourne Symphony Orchestra in 1988, he was a member of the Queensland Theatre Orchestra from 1982 to 1984, the Queensland Symphony Orchestra from 1984 to1987, and the State Orchestra of Victoria (now Orchestra Victoria) from 1987 to 1988.
Keith is married to MSO violinist Christine Johnson and they have three children. He enjoys computers and is a keen amateur meteorologist. For recreation he likes walking, playing squash and lawn bowls.