Junk Music is an unreleased instrumental recorded on 5 January 1986 during the seven-hour so-called "Everybody's Jam" session at Sunset Sound, Hollywood, CA, USA that also produced Groove In C Minor, Slow Groove In G Major, Groove In G Flat Minor. Two more titles associated with this session, Up From Below and Y'All Want Some More?, are in fact parts of the full length over 60-minutes long jam known as Junk Music, while a half an hour long jam on For Love was also part of the "Everybody's Jam". For Junk Music, Prince primarily played drums.
An edited 19-minute version of the track was to be included as the first track on the 22 January 1986 configuration of a proposed The Flesh EP, to be credited to The Flesh (taking up the entire first side of the proposed vinyl release), which was ultimately abandoned. The parts later titled Up From Below and Y'All Want Some More? were to be on the b-side of this EP.
30 seconds of the track was included as background music on Under The Cherry Moon, in the scene where Christopher Tracy races against Mary Sharon on the horse race track.