|This study was conducted to investigate the characteristic factors which have been influenced on nitrous oxide (N2O) emissions related to the environment change of nitrogen application level, rainfall and temperature during the potato cultivation at black volcanic ash soil from 2010 to 2011. During the potato cultivation, the more amount of nitrogen fertilizer applied, N2O emissions amounts were released much. N2O emissions with the cultivation time were released much at the first and middle of cultivation with heavy rainfall, but it was released very low until the end of cultivation and drought season. N2O emissions mainly were influenced by the rainfall and soil water content. The correlation (r) with N2O emissions, soil wate, soil temperature in 2010 were very significant at 0.6251** and 0.6082** respectively, but soil EC was not significant to 0.10824. In 2011, soil temperature was very significant at 0.4879**, but soil water and soil EC were not significant at 0.0468 and 0.0400 respectively. Also, NH4-N was very significant at 0.7476**, but NO3-N and soil nitrogen (NO3-N + NH4-N) were not significant at 0.0843 and 0.1797, respectively. During the potato cultivation period, the average emissions factor of 2 years released by the nitrogen fertilizer application was presumed to be 0.0040 (N2O-N kg N-1 kg-1). This factor was lower about 2.5 times than the IPCC guideline default value (0.0100 N2O-N kg N-1 kg-1).