Wabash Township is one of twelve townships in Jay County, Indiana, United States. As of the 2020 census, its population was 542 inhabitants (down from 578 inhabitants from 2010) and it contained 168 housing units.
The Grouping of Religious Buildings at Trinity was listed on the National Register of Historic Places in 1980.
According to the 2010 census, the township has a total area of , of which (or 99.87%) is land and (or 0.13%) is water. The streams of Franks Drain, Loblolly Creek and Wilson Creek run through this township.
The township contains one cemetery, Stevenson.