make an assessment of plant diversity, plant community types, structural analysis of woody plantrnspecies and quantify the amount of carbon stock and its relation with environmental gradients. Arnsystematic sampling technique was used and a total of 102 and 30 sample plots each with 20 x 20rnm were laid along the altitudinal gradient for Gergeda and Anbessa forests, respectively. FromrnGergeda forest a total of 178 plant species that belong to 150 genera in 71 families werernidentified, out of which 45.5%, 12.92%, 11.23% and 30.33% were trees, shrubs, climbers andrnherbs, respectively. Fabaceae was the most abundant family followed by Asteraceae,rnAcanthaceae, Celastraceae and Poaceae. From Anbessa forest a total of 118 plant species werernidentified which belong to 93 genera in 46 families. Out of these, the percentage of trees, shrubs,rnclimbers and herbs were 33.05%, 11.86%, 11.86% and 43.22%, respectively. Fabaceae was thernmost abundant family followed by Asteraceae, Poaceae and Lamiaceae. The present studyrnreported 13 and nine endemic plant species are present in Gergeda and Anbessa forests,rnrespectively. Moreover, 44 and 29 plant species were recorded as new records for Wellegarnfloristic region from Gergeda and Anbessa forests, respectively. The structures of woody plantrnspecies in the two forests were also computed and six general population structure patterns werernrecorded from each forest. Four plant communities from each Gergeda and Anbessa forests werernidentified. In Gergeda, Pouteria adolfi-friedericii – Syzygium guineense community was both thernmost diverse (Hʹ=4.43) and species rich community with 87 species; whereas Arundinaria alpinarndominated community was the least diverse (Hʹ=0.15) and the least species rich community withrnfive species. In Anbessa forest Combretum collinum - Dombeya quinqueseta -Securidacarnlongepedunculata community was the most diverse community while it has 12 species. Whereas,rnOxytenanthera abyssinica - Combretum molle - Syzygium guineense subsp. macrocarpumrncommunity was the lease diverse with Hʹ 0.16, while it was the most species rich community withrn30 species. The mean total carbon stock density of Gergeda forest was found to be 717 tonsrnCarbon ha-1, out of which 466, 93, 2.5 and 155 tons Carbon ha-1 were stored in the above ground,rnbelow ground, litter and as soil organic carbon, respectively. The mean total carbon stock densityrnof Anbessa forest was also found to be 353 tons ha-1 Carbon, out of which 169, 34, 1.15 and 149rntons of Carbon were stored in the above ground, below ground, litter and as soil organic carbon,rnrespectively. The one way analysis of variance showed that, there is a significant diiferencernbetween different carbon pools at both forests. Environmental gradients also showed a significantrninfluence on the amount of carbon stored in the different pools. Altitude and aspect stronglyrninfluences the amount of carbon stored in plants. Visualization model of Altitude verses carbonrnstock showed a bell shaped structure, which implies that carbon stock increases as altitudernincreases and then reaches to its peak around 2250 m.a.s.l. and turns down while altitudernincreases beyond this. The two forests can play a significant role in biodiversity conservation asrnwell as climate change mitigation, since they can sink 35,612,861 and 5,329,610 tons of Carbon,rnrespectively.rnKey words/phrases: Plant diversity, floristic composition, forest structure, carbon sequestration and environmental gradients.