Etna
- County:
- Siskiyou County
- County Seat:
- No
- Area (mi²):
- 0.766
- State:
- California
Etna is a city located in Siskiyou County, California. Etna has a 2026 population of 643. Etna is currently declining at a rate of -1.23% annually and its population has decreased by -4.6% since the most recent census, which recorded a population of 674 in 2020.