Kate Winslet is an English actress who has occasionally lent her voice to animated films, including the English-language dub of the anime feature Mary and The Witch's Flower. While she is globally renowned for her extensive work in live-action cinema, her contribution to anime is specific to providing voices for English-dubbed versions of animated films, rather than performing in original Japanese-language productions.

In the 2017 animated film Mary and The Witch's Flower, produced by the Japanese studio Ponoc, Winslet voiced the character Madam Mumblechook. Madam Mumblechook is the headmistress of Endor College, a school for magic, and serves as a primary antagonist in the story. The English-language adaptation featured a cast of prominent British actors, with Winslet starring alongside Ruby Barnhill as Mary and Jim Broadbent as Doctor Dee.

Beyond this role, Winslet's work in voice acting has been primarily for English-language animated productions. This includes voicing the character Rita in the 2006 Aardman Animations film Flushed Away and providing a voice for the 2001 animated film Christmas Carol: The Movie. For the latter, she also performed the song "What If?" for the soundtrack. Her contributions to the audiobook Listen to the Storyteller earned her a Grammy Award.