Hayley Kiyoko Alcroft (/ˈheɪli kiˈjoʊkoʊ ˈælkrɒft/ HAY-lee kee-YOHK-oh AL-kroft; born April 3, 1991), known professionally as Hayley Kiyoko, is an American actress, singer, and songwriter. She is best known for playing Velma Dinkley in Scooby-Doo The Mystery Begins and Curse of the Lake Monster, as well as Stella Yamada in the Disney Channel film Lemonade Mouth.

She portrayed the role of Raven Ramirez in CSI: Cyber and currently has a main role on the spin-off web-series of The Fosters.

In addition to various releases with the pop group, The Stunners, Kiyoko has issued two solo EPs: A Belle to Remember (2013) and This Side of Paradise (2015).