The biomass and the contents of 9 nutrient elements and their accumulation,distribution and biological cycling of the Alnus formosana plantation have been studied in Laizhou experimental forest farm of Fujian province.The results included:(1)the total stand biomass was 285.8 t/hm 2 ,of which trees accounted for 93.24%;The net primary productivity of the whole stand was 36.05 t/(hm 2 ·a).(2)the different organs of A.formosana stand had different nutrient contents.The order of total contents in different organs was nodules>leaves>fruits>barks>branches>roots>stems without barks.The order of average content of different nutrients was Ca>N>K>Mg>Fe>P>Mn>Zn>Cu.(3)the total accumulation of 9 elements in the plantation was 4 813.54 kg/hm 2 ,of which the aboveground part and the underground part accounted for 83.4% and 16.6% respectively.The amount of uptake,retention and return of 9 elements in the plantation were 1 181.48 kg/(hm 2 ·a),534.87 kg/(hm 2 ·a) and 646.61 kg/(hm 2 ·a) respectively.(4)the cycling coefficient,utilization coefficient and circulation period were 0.25～0.64,0.23～0.69 and 3.96～9.7 respectively.