JCO

JCO as an acronym may stand for:


 * JCO (company), a Japanese nuclear fuel cycle company involved in the Tokaimura nuclear accident
 * Jamaican Caves Organisation
 * Jewish Combat Organization, a Jewish resistance group during World War II
 * Journal of Clinical Oncology, a medical journal
 * Joyce Carol Oates, American author
 * Junior commissioned officer, a group of military ranks in the armies of India, Pakistan, and Bangladesh
 * Junkers, a former German aircraft manufacturer