Abstract. Bareke T, Addi A. 2021. Allometric equation for aboveground biomass estimation of Galiniera saxifraga (Hochst.) Bridson in Gesha-Sayilem forest, southwestern Ethiopia. Asian J For 5: 76-82. There is limited information about the precise quantification of Aboveground Biomass (AGB) of species-specific allometric equations for shrubs and small trees. Thirty Galiniera saxifraga plants were selected to develop species-specific allometric biomass equations. Biometric parameters, including the diameter at the Breast Height (DBH), height and crown area were predictive variables that were measured for each individual plant. AGB was measured through a destructive method. The AGB was correlated to biometric variables using regression analysis. The species-specific allometric models, with DBH and crown area as predictors (DBH-crown area models), accounted for 90% of the variation in the AGB of G. saxifraga. The DBH-crown area model was adequate for predicting the AGB for G. saxifraga with the adjusted R2 value 0.9 and AIC values was 47.37. The specific allometric equation developed for the Gesha-Sayilem Afromontane forest can be used in similar moist forests in Ethiopia to implement Reduced Emission from Deforestation and Degradation (REDD+) activities to benefit the local communities from carbon trade.