* Duchess: The elegant mother cat.
* Berlioz: The mischievous and musical kitten.
* Marie: The beautiful and refined kitten.
* Toulouse: The adventurous and playful kitten.
* Thomas O'Malley: The streetwise alley cat who helps the family.
* Scat Cat: The leader of the alley cat jazz band.
* Squeeks: The nervous little alley cat.
* Roquefort: The family's loyal dog.
* Edgar: The evil butler who plots to get rid of the cats.
There are also several other cats in the film, including the alley cats who play in Scat Cat's band, and the cats who live in the house with Edgar.