Nitrogen mineralization was investigated in controlled conditions (60% WHC, 20°C) in the soil of some alpine grassland communities. A significant correlation was found between the mineralization of nitrogen and certain soil factors (pH, WHC, Total Nitrogen and Organic Carbon). It was concluded that ammonification takes place at higher rates in grasslands which are dominated by Nardus stricta L. (Poaceae) plant species, whereas nitrification occurs at a higher rates in grasslands which are dominated by Festuca cyllenica Boiss. et Heldr. and F. punctoria Sm. (Poaceae).