Kumiko Nishihara is a Japanese voice actress from Chigasaki, Kanagawa affiliated with Aoni Production also known for her work on the stage.
While a student at Wako University, Nishihara attended voice acting classes run by Kaneta Kimotsuki. When Kimotsuki established Theater Company 21st Century Fox (劇団21世紀FOX, Gekidan Niju Isseiki Fox) in 1984, Nishihara went on to leave her undergraduate studies unfinished to become a founding member, taking numerous roles as a leading actress in several productions and appearing in the lead role of Alice from Alice in Wonderland three times. Theatre Company 21st Century Fox became known for producing numerous voice actors with a theatre background such as Kaneta, Nishihara, and Kappei Yamaguchi.
Nishihara took on voice acting roles in anime starting with Little Memole and becoming known for major voice acting roles in anime such as Hello! Lady Lynn, Sailor Moon Sailor Stars, and s-CRY-ed, in addition to voice acting roles in a number of Japanese games. Nishihara is known for taking on voice acting roles involving high pitched female voices and a great deal of singing, leading to appearances on the Japanese music variety show Utaban aired by the Tokyo Broadcasting Corporation.