Jim Hopkinson studied music in Paris and London and won a scholarship to the Royal College of Music, becoming its youngest student. He was subsequently appointed as the second flautist in the London Philharmonic Orchestra under Sir Thomas Beecham in 1934. From 1936 to 1948, he played in the BBC Symphony Orchestra and during the Second World War, he served in the entertainment section of the RAF. Hopkinson worked in the New Zealand Broadcasting Corporation Symphony Orchestra from 1949 to 1963 and then in the Melbourne Symphony Orchestra until he settled in Perth in the late 1960s.
In Perth, Hopkinson conducted the Karrinyup Symphony Orchestra, gave flute lessons, was a sessionist flautist with the WA Symphony Orchestra and was a librarian for ABC Television.