Sayaka Aoki is a Japanese voice actress born on October 19, 1972, in Akita Prefecture. She is affiliated with Bell Production management and has also worked under the name Shizuka Aoki for stage performances. Aoki possesses a naturally high-pitched voice, which she has frequently employed to portray young girls, Lolita-style characters, and heroines in adaptations of bishōjo games and anime.

Aoki's career includes a wide range of roles in anime television series, original video animations, and video games. Her filmography demonstrates a recurring collaboration with the Lime-iro Senkitan franchise, where she voiced the character Kinu Fukushima in the 2003 television series, its 2004 OVA sequel, and related video games, as well as performing theme songs for the series. Another notable recurring role is her portrayal of Lisianthus, also known as Kikyo, in the anime adaptations of the Shuffle! visual novel, including the 2005 series and the 2007 sequel Shuffle! Memories. She is also known for voicing Minatsu Amakase and the character Harimao in the Da Capo II anime and its second season, returning to the role of Minatsu for Da Capo III in 2013.

Some of her most widely recognized roles include Kyon's younger sister in the immensely popular The Melancholy of Haruhi Suzumiya series, a role she reprised for its 2009 renewal, the 2010 film The Disappearance of Haruhi Suzumiya, and the 2015 spin-off The Disappearance of Nagato Yuki-chan. Aoki also voiced Miria Harvent in the acclaimed 2007 series Baccano!. In the video game world, she has had a long-running association with the Sonic the Hedgehog franchise, voicing the character Cream the Rabbit across numerous games and the anime series Sonic X since 2003.

Her other significant voice roles include Wakaba Fujimiya in Wind: A Breath of Heart (2004), Ou in Tayutama - Kiss on My Deity (2009), Alice in We Without Wings - Under the Innocent Sky (2011), Sae Nagumo in the Saishū Shiken Kujira OVA and net animation, Yayoi Amenomori in Nanatsuiro Drops (2007), Sumire Aso in the Ef: A Fairy Tale of the Two series (2007), and the Fairy in Humanity Has Declined (2012). Aoki's career also includes work in OVAs such as 15 Bishōjo Hyōryūki, where she voiced Kageko Satake.