Abstract: Ecosystem carbon storage and its allocation in soft broadleaved forests were investigated across Guangxi Zhuang Autonomous Region. In total, 42 plots, each with an area of 1000 m², were selected. The plots covered five stand ages, i.e., young forest, middleaged forest, pre-mature forest, mature forest and overmature forest. The results showed that total ecosystem carbon storage ranked in the order of mature forest (421.98 t·hm^-2) > overmature forest (405.23 t·hm^-2) > pre-mature forest (218.74 t·hm^-2) > middleaged forest (172.94 t·hm^-2) > young forest (164.20 t·hm^-2). Carbon storage in different ecosystem compartments across different stand ages varied in the order of soil layer > aboveground layer > litter layer, except the mature forest for which carbon storage in the aboveground layer was greater than that in the soil layer. When carbon storage in the soil layer and litter layer was combined, carbon storage in the belowground part was greater than that in the aboveground part. However, the mature forest was an exception for which carbon storage in the aboveground part was greater than that in the belowground part. The carbon storage of the aboveground layer ranged from 32.03 to 222.43 t·hm^-2, which accounted for 30.03%-55.28% of the total carbon storage and increased with stand age. The carbon storage of litter layer ranged from 1.51 to 3.58 t·hm^-2, which accounted for 0.69%-1.56% of the total carbon storage and showed an “M” type trend. The carbon storage of soil layer ranged from 117.33 to 294.54 t·hm^-2, which accounted for 44.06% to 75.69% of the total carbon storage and increased with stand age. The largest carbon pool for the aboveground layer was tree layer (ranging from 27.53 to 220.50 t·hm^-2), which accounted for 16.77%-54.41% of the aboveground layer carbon and increased with stand age. The largest carbon pool for the tree layer was in trunk (ranging from 16.99 to 167.91 t·hm^-2), which accounted for 61.70%-76.15% of the carbon storage in the tree layer and increased with stand age. The proportions of roots and leaves ranged from 9.07% to 18.60% and from 1.59% to 6.62% of the aboveground carbon pool respectively, and decreased stand age. Carbon storage in the branch ranged from 3.08% to 13.41% of the aboveground carbon pool and showed a trend to decrease with stand age.