Ado Mizumori is a Japanese voice actress, singer, illustrator, and performer born on December 23, 1939, in Tokyo, Japan. Her career as a voice actress is closely tied to the animated films of Toei Animation, where she was part of a recurring trio of voice actors.

Mizumori is best known for her role as one of the three bumbling feline assassins, specifically the character Killer C or the Little Assassin, in the Puss 'n Boots film series. She first played this role in the 1969 original film Puss 'n Boots. She reprised the same character in the sequels, including Three Musketeers in Boots in 1972 and Puss in Boots: Around the World in Eighty Days in 1976. In these films, she consistently performed alongside voice actors Shun Yashiro and Isamu Tanonaka, who voiced the other two assassins.

Beyond the Puss 'n Boots series, her voice acting credits extend to international co-productions. In the 1978 animated television special The Stingiest Man in Town, an adaptation of A Christmas Carol, she provided the voice for the character Martha Cratchit.

In addition to her voice work for characters, Mizumori performed theme songs and insert songs for numerous anime series throughout the 1970s and 1980s. Her musical credits include performance work on popular franchises such as Dr. Slump and Arale-chan, Panda! Go, Panda!, and Secret Akko-chan.