Etna-Troy Township is one of nine townships in Whitley County, Indiana, United States. As of the 2020 census, its population was 1,863 (down from 1,889 at 2010) and it contained 875 housing units.
Etna Township, which was annexed by Whitley County from Noble County in 1860, merged with its neighbor to the south, Troy Township, in 1951.
According to the 2010 census, the township has a total area of , of which (or 97.64%) is land and (or 2.36%) is water. Lakes in this township include Goose Lake, Indian Lake, Little Troy Cedar Lake, Loon Lake, Mud Lake, New Lake, Old Lake, Rine Lake, Robinson Lake, Scott Lake, Tadpole Lake, Troy Cedar Lake and Winters Lake. The stream of Cedar Lake Branch runs through this township.
(This list is based on USGS data and may include former settlements.)
The township contains four cemeteries: Adams, Kiester, Pleasant Grove and Scott.