NKA

NKA may refer to:
 * "Now known as"
 * "No known allergies" in medical jargon
 * Initialism for North Korean Army, also known as the Korean People's Army
 * Na+/K+-ATPase, an enzyme located in the plasma membrane in all animals
 * Karate Canada, previously the "National Karate Association" of Canada
 * New Kosovo Alliance, a political party
 * Neurokinin A, a neurologically active peptide that seems to be involved in reactions to pain and the inflammatory responses