Soil organic carbon density in forest plays a dominant role in global carbon cycle and balance.Exploring the influence of the interaction of multiple factors on soil organic carbon density has important significance to assessment of soil organic carbon storage,scientific prediction of climate change and strategies to address climate change.This study,based on national forest inventory plots,choosing typical sample plots to carry out surveys and soil sampling,studied the effects of many factors on soil organic carbon density.The results showed that forest type,age group,altitude,aspect,slope position,soil type were dominate factos affecting soil organic carbon density.Anestimation model between six dominant factors,mamely,forest type,age group,elevation,aspect,slope position,soil type was established.