Abstarct: Abstract Phosphate and nitrate are among the most crucial anionic water pollutants. Excessive entry of these compounds into water causes eutrophication and damage aquatic ecosystems and other living organisms while promoting algae growth. The present study has studied the synergistic effect between reduced graphene oxide (rGO) and zero-valent iron nanoparticles (nZVI) on removing phosphate and nitrate from aqueous solutions. Wheat and rice husks were used as agricultural wastes for GO synthesis. The rGO-nZVI composite has been synthesized by a green method using green tea extract. UV-Visible, XRD, SEM, EDS, FTIR, and zeta potential characterization confirmed the successful formation of the composite. A comparison of phosphate adsorption results with GO and rGO-nZVI adsorbents showed that the synthesized composite improved the adsorption properties of GO. The rGO-nZVI composite also showed significant and effective results in nitrate adsorption. The effect of various adsorption parameters, including initial concentration, adsorbent dosage, contact time, and pH, was studied. The maximum removal efficiency of phosphate and nitrate was 77.63% and 62.59%, respectively, at the initial concentration of 25 mg/L of the anions. The optimal adsorbent dosage for the removal of phosphate and nitrate was 10 g/L. Estimating adsorption isotherm and kinetic for both anions followed Freundlich and pseudo-second-order models, respectively. The maximum adsorption capacity obtained from the Langmuir model for phosphate and nitrate was 16.99 and 107.9 mg/g, respectively. Phosphate has lower reversibility than nitrate due to its specific adsorption. The rGO-nZVI composite is promising in the water treatment industry due to its ability to reduce phosphate and nitrate in water.