AbstractMagnetic Fe3O4 nanoparticle decorated graphene oxide (GO) was modified with strontium nanoparticles (MGO‐Sr) and applied for enhanced removal of phosphate and nitrate ions from river and sewage water samples. The nanocomposite's features were investigated using Fourier transform‐infrared spectrometry, field emission‐scanning electron microscopy, energy‐dispersive X‐ray spectroscopy, and X‐ray diffraction. The effective parameters, adsorption efficiency, regeneration, and field application of MGO‐Sr were also studied. Adsorption isotherm and kinetic models were applied for evaluation of experimental adsorption process. The data was in well comply with Langmuir isotherm and pseudo‐second‐order comparing with other models. Langmuir maximum adsorption capacity was obtained equal to 238.09 mg/g for phosphate and 357.14 mg/g for nitrate. Van't Hoff thermodynamic predicted an exothermic nature for adsorption process followed by a physisorption mechanism. The prepared nanocomposite provided a high‐removal efficiency toward phosphate and nitrate ions in river and sewage water. Hence, it is applicable in water remediation process.