Forests play a significant role in sequestering greenhouse gases and reducing climate change. However, forest resource degradation is increasing from time to time. Hence it is important to investigate the biomass carbon stock and analyze the forest cover dynamics because there is a carbon trade business in which the countries charged based on the stored greenhouse gasses that could serve as a financial source to run a sustainable community-based forest management system. This study was conducted to investigate carbon stock and land use land cover dynamics of the Alemsaga forest and its surrounding area in north-western Ethiopia. A transect survey method was used to sample the carbon stock. The sampling point has a distance of 500m from each other resulting in a total of 34 points for forest biomass and 10 sample points were selected randomly for the forest SOC sample. Also, five sample points for each land use type (grazing land and cultivated land) were allocated randomly for the SOC sample. The circular sample quadrant was used to collect biomass sample, the radius of 0.56m was used for herb, litter, and soil sample, while 6.4m radius of the circular plot was for measuring trees with D.B.H. <15cm. Whereas 10m radius of the circular plots were used for measuring tree with D.B.H >15cm. The land use/cover classification and change analysis was conducted using a free 30m*30m pixel size/spatial resolution of the Landsat image (ETM+). To quantify the trend of land-use/cover composite Landsat satellite images for the year (2000, 2010, and 2018) were used and analyzed using ArcGIS version 10 software. The result shows that there were 60 types of species and 2209 individuals of the tree were recorded in 34 sample plots. The tree species distribution in Alemsaga forest was dominated by some shrub species such as Carissa edulis (12.79%), Dodonaea Angustifolia (9.96%), Premna schimperi (5.30%), Achanthus sennii (4.17%) Grewia ferruginea (3.77%) Clausena anisata (3.32%) and Clutia abyssinica (3.10%) Based on the plant height class categories the majority of the samples were found in the lower height class 1 (<5m) and class 2 (5-10m), similarly, the lower DBH and height class consists of the majority of (90.18%) tree individuals, also the lower biomass carbon stock as well. The higher biomass carbon stock was recorded in higher DBH and height class but less in tree density. The mean AGB carbon stock of the forest land-use system was 64.95±24.86 t/ha while the mean soil organic carbon stock of the forest was 64.1±2.4 t/ha in 30cm soil depth. The SOC stock analysis among the three land-use systems within the soil depth of 0–10cm, 10-20cm, and 20-30cm shows a significant difference between the land use system and soil depth. The soil depth of 0–10cm, 10-20cm, and 20-30cm have (92.87±4. 62.57±9.47, 36.87±8.21 t/ha) in forest land, while the grazing land mean SOC stock was (57.88±7.02, 45.89±5.16, 35.24±4.03 t/ha), and the cultivated land mean SOC was (41.46±3.25, 32.52±4.32, 28.76±4.2t/ha) respectively. Alemsaga forests cover has been increased in the last couple of decades, the forests covered including the spares and the dense forest was 664.15hectare of land before 18 years ago in 2000, but currently, both land class covers 811.56 ha in 2018. The improvement of forest land status was directly related to the government and stakeholder involvement in forest management intervention. Whereas, the bush land class in 2000 was 194.43 ha and further reduced to 137.86ha (9.20%) in 2018 because the community expands their farm by converting the grazing land into cultivated land. The government should give more emphasis on forest protection and consider carbon trade and planting a tree species which has higher carbon sequestration capacity. Keyword: Biomass carbon stock; SOC stock; LULC change