Globally forests contribute for about 80% of terrestrialbiosphere carbon storage that indirectly played a paramount importance in mitigation of global and local climate. Theecosystem of Lake Tana sub basin is one of the richest ecosystems and holds old aged church forests. Churches along the basin of the lake are endowed with rich biodiversity of forest species that can store huge carbon stock. However the role of church forest for above ground carbon stock is not well studied by integrating remote sensing and ground based data in time and space. The focus of this study was to investigate the role of church forest for carbon storage using satellite data and ground based measurements in Taragedam and Zegie peninsular church forests.Field data measurement from these trees having a DBH of 10m and above, and tree height having 10m and above with their corresponding specific wood densities were taken from the 52, 20x20m sample plots being selected by systematic random sampling were used to collect biometric data from Tara Gedam and Zegie church forests. This data was correlated with seven Sentinel 2A level 1c imagery data derived vegetation indices of 2020 to get model and to estimate of AGB and their by AGC of 2020. Landsate 5 TM data of 1985 and 2000 with sentinel 2A data of 2020 was applied to investigate carbon stock change by applying hotspot analysis. The result revealed that the AGB calculated from field data and selected indices show a good correlation result (from r=0.866 and R2=0.65(VDVI) to r=0.95 and r2=0.82(NDVI). The model result shows 5.01 to 22.9 (mean=10.8) ton per pixel AGC was stored in Zegie and 2.501 to 27.9 (Mean =12.616) ton AGC stored in Tara Gedam per pixel in 2020. In Zegie -19-14.5 ton, -17 to 22.7 ton and -21 to 19 to AGC change was observed in 1985 to 2000, 2000-2020 and 1985 to 2020 respectively. In Tara Gedam -25 to 20.8 ton, -15 to 22.6 ton and -22.2 to 26.6 ton AGC changes were observed.The hotspot analysis result shows that in Zegie, addition 8.3 ton and loss of 15.8 ton per pixel AGC was recorded from 1985 to 2000. From 2000 to 2020 there was increase of 17 ton and decrease of 4.8 to per pixel AGC. In this site from 1985 to 2020 a loss of 12.1 ton and gain of 15.6 ton per pixel AGC was obtained. In Tara Gedam site from 1985 to 2000 a gain of 15.8 to and loss of 14.3 ton AGC was detected. The gain and loss was 21.7 ton and 2 ton per pixel from 2000 to 2020. From 1985 to 2020 a gain of 29.3 ton and loss of 9 ton per pixel was obtained. This study concluded that NDVI was best vegetation indices that had a strong correlation with field AGB and provide robust result (R 2 = 0 821). The AGC predicted in 2019/2020 was 271 ton ha-1 in Zegie and 315 ton ha-1 in Tara Gedam. The hotspot analysis result concluded that gain of 29.3 ton and 14.6 ton pixel-1 of AGC estimated across hotspot boundaries 1985-2020 in Tara Gedam from and Zegie church forests respectively. However, 9 ton and 12.1 ton pixel-1 loss of AGC was predicted in Tara Gedam and Zegie respectively across cold spot boundaries from 1985-2020.Based on this result better above ground carbon estimation will be achieved if the microwave remote sensing (like Radar, InSAR) integrated with field data. Key Terms:Above Ground Carbon, RegulatingEcosystem service, Church Forest