In order to understand the carbon sequestration of ecological forests in Loess Plateau of Gansu Province,we toke the different slopes (sunny and shady slope)and restoration duration(conversion of 6 years,9 years and 12 years) of Pinus tabulaeformis plantations as test objects and by the methods of plot investigation and biomass measurement.We studied the carbon content in different plant organs,shrub layers,grass layers,litter layers and soil layers and the carbon storage and its allocation in tree layer,shrub layer,grass layer,litter layer and soil layer.For the test plantations,the carbon storage content in different P.tabulaeformis organs ranged from 48.15%~53.90%,which in the order as follows:stem>leaf>fine-branch>thick-branch>stump>thick-root>bark>large-root>medium-root>small-root>fine-root>cone;in shrub layer was stem>leaf>root;in grass layer was abovegrond>underground;in litter layer was fresh>decomposing.The carbon storage in the soil profiles(0~100 cm) increased with plantation age but decreased with soil depth.There are significant different of difference slope positions in 0~10 cm and 10~20 cm.The total carbon storage in sunny and shady slopes of the 6-,9-and 12-year plantations was 42.90,50.50,59.22 t·hm^-2 and 45.08,53.77 and 65.70 t·hm^-2.It was considered that P.tabulaeformis had a good carbon sequestration function in sunny slope and shady slope.The shady slope was better than sunny slope and being able to be an ideal tree species in Loess Plateau of Gansu Province.