Casca could be:
- CASCA: The Canadian Astronomical Society
- CASCA: The Canadian Anthropological Society
- Servilius Casca, one of the assassins of Julius Caesar
- Casca (character of Rome), a character in the HBO television series, based on Servilius Casca
- Casca (series), a series of paperback novels about an immortal soldier named Casca Rufio Longinius, based loosely on the Longinus legend of Christianity
- Casca (grape), another name for the wine grape Mourvèdre
- Casca, Rio Grande do Sul, municipality of Brazil
- Casca District, in Peru
- Casca, a character in the anime and manga series Berserk