Saeko Chiba (千葉 紗子) is a prolific seiyū (voice actress) and singer who was born on August 26, 1977 in Hachinohe, Aomori, Japan, and grew up in Tokyo. She is contracted to Space Craft Produce, a branch of Space Craft Group.

Saeko Chiba took up ballet at a young age with ambitions of becoming part of Takarazuka Revue. However, having failed the entrance exam for Takarazuka Music School in her third year of middle-school she joined the Minami Aoyama Shōjo Kageki Dan (南青山少女歌劇団, South Aoyama Female Opera Group?, also called Nanshō for short) a stage group for teenage girls.

Having had several lead roles over the three years she spent with the troupe, Saeko was then cast in the lead voice acting role of Kotori Haruno in the Sega Dreamcast game Kita e. ~White Illumination. Having had a taste of being a seiyū and deciding that she preferred voice acting to performing on stage, Saeko decided to pursue the career full-time.

Some of her earlier roles include Tsubaki Sakura in Kare Kano, Kitsune no Akane in Angel Tales and Elliot Chapman in Sci-fi Harry. Saeko was famed for her long, straight black hair and seemingly cold outward appearance which led to her being cast in various tsundere and 'cool-girl' roles. She then cut her hair short in the spring of 2005 which strangely coincided with the increasing diversity of her roles, as Saeko herself noted on the Mai-HiME fandisc interview.

Saeko has also pursued a singing career, with Yuki Kajiura (who wrote music for some of the Nanshō stage shows) writing and producing almost all her material. Her first single was Koi no Kiseki, the theme song for the PlayStation game Meguri Aishite. She has since released nine singles and two albums, along with various character song and drama CDs.

Saeko was also part of the group tiaraway with fellow Nansho member Yuuka Nanri. Originally recording and performing as Saeko Chiba & Yuuka Nanri for the game/anime Memories Off 2nd, the duo released three singles and an album before breaking up on 6 March 2005.