Maid Deka (メイド刑事（デカ）, Meido Deka, "Maid Detective") is a Japanese light novel series written by Yūji Hayami and illustrated by Kiyotaka Haimura. The first novel was released on April 15, 2006, and as of July 15, 2009, nine volumes have been published by SoftBank Creative under their GA Bunko imprint.

A manga adaptation by Michiko Usami was serialized on Flex Comix's free web comic FlexComix Blood and FlexComix Next. A TV drama adaptation aired in July 2009 on TV Asahi.