Risa Wataya (綿矢 りさ Wataya Risa, born February 1, 1984) is a female Japanese novelist from Kyoto.
She rose to fame in 2003 upon receiving the Akutagawa Prize for her short novel Keritai Senaka ("The Back You Want to Kick"), while at Waseda University. The prize was shared between Wataya and Hitomi Kanehara, another young, female author. At the age of 19, Wataya became the youngest author—and the third student—ever to receive this greatly prestigious award, the first two student winners having been Shintarō Ishihara and Keiichiro Hirano.
Wataya's works have been translated into German, Italian, French, and Korean.
In 2004, her novel Install was adapted into a film starring Aya Ueto.