Buttercup’s dress is green in the original series The Powerpuff Girls.
Buttercup is the trio’s dark-green-dressed member and is commonly characterized as the toughest and most aggressive of the three sisters. Her color helps viewers distinguish her immediately from Blossom’s pink and Bubbles’ blue.
The girls’ simple, matching costume design uses color, hairstyle, and personality to create clear visual identities. Buttercup has short black hair, a green dress, and a green bow, while her sisters use contrasting colors and silhouettes.
Color associations can vary in merchandise and later adaptations, but the original animated series consistently identifies Buttercup with green. The color is a design feature rather than a statement that she has green skin; all three girls have the same light skin tone in the original show.