CMK (disambiguation)

CMK may refer to:
 * Central Milton Keynes, the central business district of Milton Keynes, Buckinghamshire, England
 * Centralna Magistrala Kolejowa, a long railway line in Poland
 * cmk, an extinct Chemakum language once spoken by the Chemakum (ISO 639:cmk)
 * Croron Mein Khel, a Pakistani gameshow aired on BOL Entertainment
 * Crabbet/Maynesboro/Kellogg, a label for specific lines of "Domestic" or "American-bred" Arabian horses
 * CMK, the former ICAO code for Chernomor-Avia, a charter airline based in Sochi, Russia