Mysterious Galaxy is an independent bookstore in San Diego, California.

It is noted for hosting book signings and readings by numerous authors of the genres.

On May 8, 1993 Terry Gilman, Maryelizabeth Hart, and Jeff Mariotte hosted the grand opening of Mysterious Galaxy with prominent authors such as Ray Bradbury, David Brin, and Robert Crais in attendance, as well as many fans of genre fiction.

[1] With the tagline "Books of Martians, Murder, Magic and Mayhem" Mysterious Galaxy has filled the niche of San Diego's most prominent genre bookstore.

[4] In 2019, Mysterious Galaxy sought a new owner and new location[5] and was subsequently purchased by Matthew Berger and Jenni Marchisotto.