Decomposition of organic nitrogenous materials in soil was affected by C/N ratio.Immobilization of nitrogen mineralized from nitrogenous material added to the soil was influenced by the degradability of carbonaceous and nitrogenous materials.The turnover of nitrogen which had been freshly immobilized in the presence of glucose in the soil was faster than that immobilized with cellulose or lignin. The effect of soil-drying on the mineralization of organic nitrogen immobilized through the decomposition of carbonaceous and nitrogenous materials in the soil depended significantly on the availability of carbonaceous materials as a microbial energy source.However, the drying effect was not always proportional to the amount of organic nitrogen accumulated in the soil.