Face It Alone was originally recorded during the British rock band’s 1988 sessions for their album The Miracle, but remained among those that did not make the final cut.
It was later rediscovered when the band’s production and archive team returned to the sessions to work on the upcoming reissue of the album.
The single is the first new song released featuring Mercury since 2014’s Queen Forever album which included three previously unheard tracks with the singer titled Let Me In Your Heart Again, Love Kills and There Must Be More to Life Than This.
The former Queen frontman died from Aids-related complications in 1991 at the age of 45.
The classic rock band – comprising of Mercury, Brian May, Roger Taylor and John Deacon – were founded in 1970 and created hit tracks together including Bohemian Rhapsody and We Will Rock You.
Speaking of the rediscovered track, May said: “I’m happy that our team were able to find this track.
“After all these years, it’s great to hear all four of us, yes, Deacy is there too, working in the studio on a great song idea which never quite got completed… until now.”
Taylor added: “We’d kind of forgotten about this track but there it was, this little gem.
“It’s wonderful, a real discovery. It’s a very passionate piece.”
The song’s arrival comes ahead of the November 18 reissue of the band’s 13th album The Miracle, first released in 1989.
The album – which included tracks I Want It All, Breakthru and The Invisible Man – reached number one in the UK at the time.
It will now be available in an eight-disc collector’s edition box set format.
Among its contents, the expanded set includes The Miracle Sessions, an hour-plus disc of further previously unreleased recordings including six unpublished songs.
It also includes the band’s spoken exchanges on the studio floor in London and Montreux, giving a revealing window into the four members’ creative process and their personal relationships.
Queen’s The Miracle collector’s edition will be available from November 18.