Wildfires are the major disturbing factor that can affect soil organic carbon content in a grassland ecosystem and may have a particularly persistent effect on the carbon stock in the affected soils. Purpose of the study performed was to investigate the carbon content and stock changes in a soil in result of wildfire occurred on the steppe of the eastern Mongolia. The results have shown that soil organic carbon content and soil organic carbon stock decreased (p<0.005) as a result of wildfire. Soil organic carbon content was highest for the unburned soil (from approximately 9.77 g kg-1 to 13.92 g kg-1 and average content is 11.27 g kg-1 in 0-4 cm) but burned soil was lower than (from approximately 6.82 g kg-1 to 9.63 g kg-1 and average content is 8.63 g kg-1). Moreover, in burned soil organic carbon stock is also 1.3 times lower than unburned soil (in 0-4 cm). In addition, topsoil bulk density increased by 0.10 g cm-3.