Abstract: The status and role of the shrub layer and main shrub species in the nutrient cycling of the mongolian oak forest were stated in this paper. The results show that the shrub layer's cycling rate is 0.68 which was more than the arbor's (0.6) and the forest's (0.64) although it is less important than the arbor layer in biomass, nutrient content, remained content, returned content etc. The shrub layer have a important role in promoting the nutrient cycling of the forest. Corylns mandshurica and Deutyia amurensis are dominant or Sub-dominat shrub species which should be protected because they Play an important role in the nutrient cycling, Acanthopanax senticasus matains more nutrient and the cycling rate is low in the nutrient cycling. It exhausted the soil but can be used as a kind of drug. So it should be protected and on the other hand should be controled.

Key words: Shrub, Mongolian oak forest, Nutrient cycling