She first appeared in "Plane Crazy", becoming a regular in the cast of original Disney characters.
Most cartoons deal with Mickey doing something embarassing that cuaes Minnie to get angry at him. This is similar to what happens with Daisy and Donald Duck, only Mickey actually tries to apologize and right whatever wrong he did, unlike Donald.
She is Daisy Duck's best friend. She speaks with a feminine version of Mickey's voice.
She appears in the final scene at Marvin Acme's factory in "Who Framed Roger Rabbit".
In "House of Mouse", she helps Mickey run the nightclub.
She appears in all three "Kingdom Hearts" videogames as Queen of Disney Castle. There, she posses most of the magical powers usually associated with Mickey.