Oak savannas in the Midwestern United States are rare ecosystems heavily altered by human activity. Common land management practices, like prescribed fire can control invasive species and restore native plants, but few studies have examined the impacts of such practices on oak savanna invertebrate communities. We examined impacts of prescribed fire on ant nesting ecology in the Oak Openings of NW Ohio. We measured ant use of natural nests and colonization of artificial nests in savannas to examine ant nest-site limitation and colonization. We collected 376 potential natural nests (362 acorns, 12 twigs and 2 other hollow nuts); 161 in burned sites and 215 in unburned sites. In burned sites, seven (or 4.34%) nests were occupied by ants and in unburned sites three (or 1.4%) were occupied, but nest occupation did not differ between burned and unburned areas. Overall 6.85% of artificial nests were occupied; 5.56% in burned and 7.59% in unburned areas, but again, the difference was not significant. Two pieces of evidence – ant use of artificial nest sites and negative correlations between natural nest occupation and natural nest availability – suggest that ants may be nest-site limited within the Oak Openings savannas. Ant richness and composition of ants found in natural nests was similar in burned and unburned areas; however, composition of ants in artificial nests tended to differ between habitats. These results suggest that burning did not impact frequency of nest occupation, or species composition of existing cavity-nesting ant colonies, but burning may alter colonization processes for cavity-nesting ants within savannas in the Oak Openings.