Abstract: Seasonal nitrogen mineralization of the soils in the evergreen broadleaf forests on Mt.Wuyi in Fujian was studied.The environmental factors affecting the process was investigated.The method of In-field Closed Tube Incubation was employed to estimate the mineralization rate.Data obtained were correlated by a regression analysis.At low temperatures,the net mineralization rate of the soil increased with rise of the temperature.After the temperature reached a high threshold,the rate began a downward trend.The seasonal change of the net ammonification rate basically paralleled that of the total mineralization rate.They were also similar in their responses to rainfall.In the region,the nitrification dominated during the dry season;while the ammonification in the rainy season.Ammonification played a determining role in the soil fertility of the evergreen broadleaf forests on Mt.Wuyi.And,rainfall was one of the important environmental factors directly affecting the soil mineralization.