CCK may refer to:
- Choa Chu Kang, a suburban town in Singapore
- Complementary code keying, a modulation technique used in IEEE 802.11b
- Cholecystokinin, a digestive hormone
- Client Customization Kit, a set of tools to aid in distributing customized Mozilla clients
- the Cocos Islands' ISO 3166-1 3-letter country code
- Communications Commission of Kenya
- Candy Coated Killahz a Canadian hip-hop/electronic music group.
- Chris Kanyon (1970–2010), a professional wrestler, also known as Chris "Campaign" Kanyon and shortened to CCK
- Composite candidate key, a candidate key comprising more than one field
- Campbell's Creek Railroad