Asen has several different meanings:
- Asen dynasty, a dynasty which ruled the Second Bulgarian Empire between 1187 and 1280
- ASEN - The Australian Student Environment Network
- Asen (artifact), a metal pole topped with a small circular alter for receiving offerings
- Asen, Asena or Ashina (clan), the ruling dynasty of the ancient Turks in mid 6th century
- Asen, the German word for Áss (singular: Ase)
- The Association for the Study of Ethnicity and Nationalism (ASEN) – an international, interdisciplinary association for academics, researchers, students, journalists and others directly concerned with advancing the study of ethnicity and nationalism
- Asen (state), a polity involved in late 17th-century wars in modern Ghana
- "Asen", an archaic unit of measurement (also aasen, aces), equal to one-twentieth of a gram, or less than .0018 of an ounce, used to value tulips, during the tulip mania
- Jaime Asensio de la Fuente (b. 1978), Spanish footballer known as Asen