The regulated loading of Fe₃O₄ nanoparticles (NPs) into a graphene nanosheet (NS) matrix along with the process of reducing graphene oxide (GO) has been achieved via a facile hydrothermal self-assembly strategy. The optimized graphene/Fe₃O₄ (GF) composite with dispersedly embedded hybridization which yields a high surface area serving as active adsorption sites and providing effective protection of the Fe₃O₄ NPs against release, aggregation, oxidation or dissolution in wastewater, as well as stable superparamagnetism allowing fast magnetic recycling. It exhibits fast Cr(VI) removal with a high adsorption capacity in acidic and neutral solutions, and the adsorption kinetics follow the pseudo-second-order model in accordance with the chemisorption in nature. Moreover, the adsorption performance shows a broad-spectrum universality to various heavy metal ions including Fe(III), Cu(II), Cd(II), etc. and has recyclability after pH-manipulated desorption, thus the GF composite has been demonstrated as a promising separable adsorbent for removing heavy metals from wastewater.