Kei Hayami is a Japanese voice actress born on December 20, 1958 in Fukuoka Prefecture, Japan. She is affiliated with the talent agency Ken Production. Hayami began her entertainment career in 1970, debuting on the NHK radio program Aozora Han Note. She initially joined the theater group Wakakusa before moving to the 21st Century FOX theater group. Her decision to pursue acting was motivated by a desire to overcome shyness and social anxiety, leading her to join a theater troupe as a child.

Hayami has built a diverse portfolio across anime, video games, and dubbed foreign productions. She is widely recognized for providing the voice of Matsuzaka Take in the long-running series Crayon Shin-chan. In video games, she is known for her role as Slippy Toad in the Star Fox series. Her anime roles include Hiroko Katsuki, the mother of the main character Yuuri Katsuki, in the series Yuri!!! on Ice. She voiced Tomoko Kido in the series Barakamon. Another notable role is Susan in the Nippon Animation television series Jeanie with the Light Brown Hair, also known as The Girl in the Wind: Jeanie with the Light Brown Hair, which aired in 1992 and 1993. Additional anime work includes roles in Detective Conan, Cardcaptor Sakura, Magic Knight Rayearth, Ashita no Nadja, and Aikatsu Friends!.

Beyond her voice work for animation, Hayami has been active in stage productions. She is a member of the theater unit FOUR ROSES, which she formed with fellow veteran actresses, including Nomura Michiko. She also participates in KenKen Park, a Ken Production project focused on reading picture books aloud for children. Hayami holds certifications as a nursery teacher, kindergarten teacher, childminder, and toy consultant. She is known for a wide range of skills and hobbies, including traditional Japanese arts such as kouta singing, shamisen, rakugo storytelling, Japanese dance, calligraphy, and flower arrangement, as well as kendo and archery. Her ability to perform numerous styles of music has earned her the nickname "human jukebox."