Ina is the southernmost village in Jefferson County, Illinois, United States. The population was 2,338 as of the 2010 census. It is part of the Mount Vernon Micropolitan Statistical Area.
Ina is located at 38°9′2″N 88°54′17″W (38.150648, -88.904709). Illinois Route 37 is the village's Main Street, and Interstate 57 runs through the west side of town, with access from Exit 83. Mount Vernon, the Jefferson county seat, is 11 miles (18 km) to the north, and Benton is the same distance to the south.
According to the 2010 census, Ina has a total area of 2.45 square miles (6.35 km2), all land.
Ina is located on high ground between Casey Creek and Gun Creek, both tributaries of the Big Muddy River. The Big Muddy has been dammed to form Rend Lake, with arms of the lake extending up the two tributaries.
Many Cherokee families settled in Ina around 1840. They were apparently refugees from the Trail of Tears.