Based on 3-year continuous field observations and laboratory analyses,the aboveground and the belowground nutrient cyclings were studied in mountainous grassland ecosystem of Jian'ou City. Each kind of nutrient content in the soil followed the order of AlFeKMgCaZnNMnP,it indicated the chemical characteristic of acid soil in the subtropics. The active elements, such as N,P,K and Ca,played an important role in the flows of material and energy because their cycle coefficients were greater than other elements like Al and Fe.In order to develope the mountainous grassland ecosystem,it was the key way to increase contents and availability of N,P,K and Ca in the soil and nutrient fluxes between vegetation and soil.Further, from the point of the soil and water conservation,suitable native grass species can be planted for increasing biomass and surface coverage in grassland ecosystem.