Arna may refer to:
- Arna, Greece - place in Greece
- Arna, Norway - place in Norway
- Arna Township, Pine County, Minnesota - place in Minnesota, USA
- Antisense RNA, or aRNA - type of DNA
- Alfa Romeo Arna - car
- Arna (moth) - species of moth
- Arna (publication) - journal of the Faculty of Arts, University of Sydney
- Arna (actress) - Tamil actress