Yūmao (ゆうまお, born on February 11, 1980) is a female Japanese singer-songwriter from Tokyo, Japan. She is a graduate of Kunitachi College of Music. She sometimes performs as an indie singer under the stage name Mayuko. Her music is produced by FlagShip and Lantis.

Yūmao is a pseudonym that she assumed in late 2002, which she uses primarily when writing and composing songs for anime and games such as Galaxy Angel and D.C.: Da Capo, as well as voice actresses such as Mai Nakahara and Ryoko Shintani. The name originated from yūmaō (優魔王), which in turn was formed from yasashii maō (優しい魔王, lit. kind devil); the long "o" sound at the end was dropped due to excessiveness.

Her two singles, "Michishirube" and "Sweet Home Song," have both been ending themes for the anime Kashimashi: Girl Meets Girl and Asatte no Houkou respectively. Additionally, her song "Kimi no Tame ni Dekiru Koto" was played in episode twelve of Kashimashi and her song "Omoide ga Hoshikatta" was released on the Please Twins! vocal album Esquisse.