The biomass and biological nutrient cycling in a Korean pine-broad leaved forest stand of Natural Reserve in the Changbai Mountains of Jilin provice were studied.Results showed that the total biomass of the stand was 210,944 kg/ha,the biomass of the above ground parts constituted 82%,and that of below ground parts 18%.lts total annual production was 7087 kg/ha,and chat of herbs was 3.43%.The contents of N,P,K,Ca 2nd Mg in the above ground biomass in the stand was 618.6,56.47,511.82,1057.95 and 75.35 kg/ha,and their amounts of annual biomass production was 78.58,7.72,45.80,84.51 and 13.97 kg/ha respectively.The percentage of nutrients uptake by trees constituted 73-92% of the total annual nutrient requirement.Althrough the biomass production of herbs only constituted 3.4% of the total biomass production,the amounts of nutrient in the production of them constituted 7-26% of the total annual nutrient require requirement to meat.