Overlord is a Japanese light novel series written by Kugane Maruyama and illustrated by so-bin. It began serialization online in 2010, before being acquired by Enterbrain. Sixteen volumes have been published since July 2012. A manga adaptation by Satoshi Ōshio, with art by Hugin Miyama, began serialization in Kadokawa Shoten's manga magazine Comp Ace from November 26, 2014. Both the light novels and the manga are licensed in North America by Yen Press since 2016.

A light novel is a type of popular literature novel native to Japan, usually classified as young adult fiction targeting teens to twenties. The definition is very vague, and wide-ranging.