Momoko Saito is a Japanese voice actress born on June 30, 1982, in Takarazuka, Hyogo Prefecture. She is a graduate of the Japan Institute of Technology College. Saito began her career after training at RAMS Professional Education and made her debut in a television anime in 2005 with a role in the series SoltyRei. In the early years of her career, she was a member of the voice acting unit Clover, formed with fellow talents from her agency. In 2008, she left her agency to work as a freelancer.

Saito is known for a voice that is often described as youthful and suited for playing young girls or childlike characters. Her filmography includes a wide range of roles across television anime, OVAs, and video games. She provided the voice for Solty Revant in SoltyRei, Choko in Chocotto Sister, and Uma in Renkin 3-kyū Magical? Pokān. In 2009, she gained further recognition for her role as Momoko Tōyoko in the long-running Saki franchise and as Sakura Shishidō in The Girl Who Leapt Through Space.

Throughout the 2010s, Saito continued to be active in the industry, taking on several notable and recurring roles. She is well-known for voicing Nazuna Takanashi in all seasons of the popular comedy series Wagnaria!! (Working!!) and its web spin-off, WWW.Wagnaria!!, in which she played Sakiko Higashida. Another significant and long-running role is Hatabō in the Mr. Osomatsu franchise, appearing in the television series, original video animations, and theatrical films. Her other anime roles from this period include Melancholy in the Phi Brain: Kami no Puzzle series, Miho Noyama in A Channel, and Perrier "Perie" La Mer in the OVA Amuri in Star Ocean. Her work also extended to video games, such as providing the voice for Thomas Shakespeare in Horizon on the Boundary.

Beyond acting, Saito's personal interests and skills include playing the flute and drawing illustrations. In 2016, she announced her marriage on her official blog.