The wonderful music for Joe 90 was by Barry Gray, who had already composed the themes and incidental music for Gerry Anderson's previous series, from Four Feather Falls to Captain Scarlet and the Mysterons, as well as the feature films Crossroads to Crime and Thunderbirds are Go. He would go on to provide the music for The Secret Service, UFO and Space: 1999 (series 1), and the feature films Thunderbird 6 (recorded between Joe 90 sessions) and Doppelgänger (released in the US as Journey to the Far Side of the Sun).

The world lost this hugely talented man more than 35 years ago on April 26th 1984, but his music lives on. For many years only a few of his original music scores had been released commercially, but Fanderson started to put that right by releasing soundtrack CDs, starting with Supercar & Fireball XL5 in 1998. These CDs are only available to club members, although they do occasionally turn up on internet auction sites such as eBay - often at vastly inflated prices, and even more often as pirated CD-R copies. If you see a CD with the words A Limited Archival Release on the cover, beware!

Silva Screen have released a series of Barry Gray CDs and vinyl records, starting with Thunderbirds on February 24th 2003. They released a 28 track CD of music from Joe 90 on May 15th 2006.