Abstract:Biomass of 14-year old Masson pine timber stands of different densities (2445–4590 trees/ha) was estimated in the hilly area in central Guangxi Province. The results show that the average biomass of individual trees decreases with increasing density within the range of given densities, Biomass of the stands was highest at Ⅱ density group (3210 trees/ha) on the contrary. On the other hand, the annual litterfall increases with increasing density, and the total accumulation of nutrient elements within litter layer increases also with increasing density.