Forest is a natural ecosystem in which litters play a major role in the nutrients return. Many factors affect the decomposition process of litter including physical and chemical environment, the quality of the litter and the population pattern of the decomposing community. This study was conducted to investigate the response of kinetic parameters of nitrogen mineralization process (determined by Stanford- Smith method) to the evolutionary level of litter in oak forest ecosystem and the possibility of estimating the kinetic parameters of nitrogen mineralization process from some N mineralization rapid indices on the oak forest litters. For these purposes, litter samples were collected in four levels, including fresh leaves (L 0 ), surface residues with low decomposition rate (L 1 ), residues with moderate decomposition rate (L 2 ) and residues with the highest decomposition rate (L 3 ) from Dalvara oak forest located in Chaharmahal and Bakhtiari province. This study was conducted in a completely randomized design with three replications. In this study, general factors of litter including electrical conductivity (EC), pH, carbon, total N and C:N ratio, nitrogen mineralization, soluble organic nitrogen (SON) and urease activity were measured. Nitrogen mineralization was measured either by Stanford-Smith methods or conventional aerobic incubations. Anaerobic index of N bioavailability was also determined. Urease activity was measured in two conditions: after sampling and after 22 weeks of incubation-leaching in the columns.. The results showed that a significant difference ( P 0.01) was observed in all measured general factors. With increasing decomposition of forest litter, EC, carbon and carbon to nitrogen ratio decreased. The highest value of EC (1.12 dS m -1 ), carbon (511 g kg -1 ) and C:N ratio (66.54) were measured at L 0 , but, pH and total nitrogen increased with increasing in litter decomposition and the highest value of pH (7.5) and total nitrogen (12.98 gkg -1 ) were observed at L 3 . As decomposition of forest litter proceeds, the rate of the amounts of N mineralized by Stanford-Smith procedure was increased ( P 0.01) and the highest rate of mineralization was observed in L 2 (N 0 = 0.15 and KN 0 = 121.47). The lowest value was obtained at L 1 (KN 0 = 34.24). The greatest and the lowest release of SON was observed in L 0 (KSON 0 = 198.42) and L 2 (KSON 0 = 102.79), respectively. The results showed that the difference in mineralization rate in the two methods of conventional aerobic and anaerobic incubation was significant ( P 0.01) and their highest values ??were at L 2 (N min anaerobic = 252 and N min aerobic = 740) and the lowest values ??were obtained at L 1 (N min anaerobic = 141 and N min aerobic = 400). Due to the significant associatio between the last week of incubation and the other incubation methods (aerobic and anaerobic) (r = 0.91 and P 0.01), the kinetic values obtained from the Stanford and Smith procedure can be successfully estimated by the two less time-consuming and labor intensive methods. The results showed that in the Stanford and Smith method, due to the high correlation between nitrogen mineralization in the final week and the tenth week (r = 0.97 and P 0.01), the experiment time can be reduced to ten weeks. The results showed that there was no significant correlation between urease activity and nitrogen mineralization. Overall, it can be concluded that the Stanford-Smith procedure can be successfully used for studying N mineralization in the litter as a different habitat. It is also concluded that the estimation of the kinetic parameters of N mineralization from N mineralized in the conventional methods are promising. The values of accumulated N mineralized at the end of 22 weeks of incubation-leaching were successfully estimated as the incubation time considerably shortened. Key Words: Forest litter, Nitrogen mineralization, Soluble organic nitrogen, Stanford-Smith method, Kinetic parameters