JCO

JCO as an acronym may stand for:

• JCO (company), a Japanese nuclear fuel cycle company involved in the Tokaimura nuclear accident
• Jewish Combat Organization, a Jewish resistance group during World War II
• Journal of Clinical Oncology, a leading medical journal
• Joyce Carol Oates, American author
• Junior Commissioned Officer, a group of military ranks in the armies of India and Pakistan
• Joint Commission Observers