Etna is a census-designated place (CDP) in Lincoln County, Wyoming, United States. The population was 123 at the 2000 census.
Etna is located at 43°2′0″N 111°0′58″W / 43.033333°N 111.01611°W / 43.033333; -111.01611 (43.031124, -111.016042). It located in Star Valley, a grassland valley surrounded by forested mountains.
According to the United States Census Bureau, the CDP has a total area of 2.0 square miles (5.1 km²), all of it land.