Lost Universe (ロスト・ユニバース, Rosuto Yunibāsu) is a series of science fiction light novels, running from 1992 to 1999, by Japanese author Hajime Kanzaka.

In Slayers, it is mentioned that the main characters of that series live in a world that is one of the four created by the mother of all creation, called the Lord of Nightmares.

A manga adaptation by Shoko Yoshinaka was published in Kadokawa Shoten's Monthly Dragon Junior magazine from December 1997 to November 2002 and was collected into four volumes.

Following ADV's bankruptcy in 2009, the rights to the anime have since transferred to Nozomi Entertainment who re-released the complete series in a new bilingual DVD box set.

The entirety of the show's English dub can be streamed and watched for free on Nozomi Entertainment's YouTube channel.