Ayreonauts Only is the first compilation album by Dutch progressive metal project Ayreon by Arjen Anthony Lucassen, released in 2000. Although categorized as a compilation album, it consists only of previously unreleased material, with alternate versions of Ayreon songs with different singers, demos, and of the song "Cold Metal" from Lucassen's then-upcoming project Ambeon.
The album's name comes from the fact that, according to Lucassen, it is "intended primarily for die-hard Ayreon fans". It is notable for featuring vocals by Ian Parry and Leon Goewie, two former bandmates of Lucassen on his former band Vengeance.