We prepared activated carbon from an agricultural waste, kuppaimeni leaf (KPL, Acalypha Indica), karuvelai leaf (KVL, Prosopis juliflora) and bottle gourd shell (BGS, Lagenaria siceraria) powders to utilize them as adsorbents for the removal of an anionic dye, Orange G (OG) from aqueous solutions. The effect of various parameters such as initial dye concentration, time, pH and temperature were investigated in the adsorption studies of Orange G dye removal. The experimental values were in good agreement with the model predicted values. Adsorption data were modeled using Freundlich and Langmuir adsorption isotherms. The adsorption of Orange G dye by activated carbon obeys Langmuir isotherm. Adsorption kinetic data were also tested using pseudo-zero, first and second-order kinetics. Kinetic studies revealed that the adsorption follows pseudo-second-order reaction. SEM results showed that the surface of the activated carbon was turned from dark to light colour after dye adsorption.