Spc. Bryant J. Luxmore, 25, was from New Windsor, Ill., which is in the western part of the state near Galesburg and the Quad Cities.
The defense department says Luxmore died Tuesday in Panjwai, Afghanistan while supporting Operation Enduring Freedom.
He died encountering enemy, small arms fire, officials said.
Luxmore was assigned to the 1st Battalion, 64th Armor Regiment, 2nd Brigade Combat Team, 3rd Infantry Division, Fort Stewart, Ga.
(The Associated Press contributed to this report.)