Abstract: Based on the measurement of biomass and the caloric values of plant samples,the standing crop of energy of a 34 year old Ormosia xylocarpa community,which is located in Sanming Xinkuo Tree Farm for teaching and research,was determined.Among the aboveground fractions ash contents and GCV and AFCV were the highest in the leaves of Ormosia xylocarpa .For the subterranean fractions,ash contents increased and GCV and AFCV decreased with the decrease of root diameter size.From tree layer,shrubs layer to herbs layer,the mean of ash content increased,while those of GCV and AFCV decreased.The standing crop of energy in Ormosia xylocarpa forest ecosystem was 4 839.20×10 9 J/hm 2,and that of the aboveground and subterranean fractions was 4 170.92×10 9 J/hm 2(86.19%)and 489.10×10 9 J/hm 2 (10.11%) respectively.96.30% of the standing crop of energy owed to tree layer.It accorded with the distribution of biomass of Ormosia xylocarpa community.