Efficient oil adsorption and recovery is a generous universal importance for future energy demand and environmental protection. Adsorbents based on 2D flatland with engineered surfaces can overcome the limitations of conventional methods for selective oil adsorption. Here, we report magnetic hydrophobic/oleophilic graphitic C3N4 nanosheets that exhibit excellent oil sorption performance and rapid removal of adsorbed oil using an external magnet. Combining porous and nanosheets structure along with magnetic FeNi3 and fatty acid surface functionalization make the system an efficient adsorbent for adsorbing and separating crude oil from water. The graphitic sheets selectively adsorb crude oil with enhancement of thickness up to 9 folds and mass by 4.5 times than the pristine nanocomposite system. The smart adsorption property of g-C3N4@FeNi3 has been realized through comprehensive adsorption kinetics and inclusive isotherm studies. The nanocomposite can be further recycled and reused in an eco-friendly manner for oil adsorption and recovery.