Aki Toyosaki (豊崎 愛生, Toyosaki Aki; born 28 October 1986) is a Japanese actress and singer. She had her first major voice acting roles in 2007, voicing Amuro Ninagawa in Kenkō Zenrakei Suieibu Umishō and Su in Shugo Chara!. She was named "Best New Actress" at the 4th Seiyu Awards in 2010 for her role as Yui Hirasawa in K-On! and Kana Nakamachi in Kanamemo, and received the "Best Lead Actress" and "Best Personality" awards at the 5th Seiyu Awards in 2011.

Her career as a musician began with her performance of the opening and ending themes of the anime series K-On! in April 2009. In the same month, she and three other voice actresses debuted as the musical group Sphere with their single "Future Stream". Later, K-On!'s ending theme was given Animation Kobe's "Best Song" award. She released her first solo single "love your life" in October 2009, and has since released two albums and eleven singles that have placed in the top 20 of Oricon's weekly charts. She was awarded "Best Musical Performance" at the 4th Seiyu Awards for her performance on the K-On! mini-album Hōkago Tea Time with four other actresses.