ABSTRACT Land surface temperature (LST) increase and urban heat islands (UHI) are significant issues in urban development. Urban green spaces are crucial in combating micro-climate change. This study assesses their effects on cooling and mitigating micro-climate change in Addis Ababa using remotely sensed data from Landsat 5 TM (1990), Landsat 7 ETM+ (2005), and Landsat 8 OLI/TIRS (2021). LST was retrieved using mono-window algorithms for Landsat 5 and Landsat 7, and the split-window algorithm for Landsat 8. Regression and correlation analyses of LST and Normalized Difference Vegetation Index (NDVI) were conducted using SPSS V23, STATA, and R Studio. Results showed a decrease in urban green space (UGS) from 120.4 km² in 1990 to 76.26 km² in 2021. Multiple linear regression analysis indicated that built-up areas and green vegetation accounted for 92.2% of LST variations. The cooling efficiency (CE) and threshold value (TVoE) of green space were calculated as 4.5 ± 0.5 hectares. This suggests that allocating green spaces of this size effectively reduces heat effects. Strengthening public participation in urban greening is crucial to mitigate micro-climate change, sustain urban development, and improve quality of life. Built-up areas and vegetation significantly impact LST more than surface water (NDWI), essential for urban green and land-use planning to minimize urbanization impacts.