A simple approach for preparing Fe3O4/graphene oxide (GO) nanocomposites through electrostatic self-assembly and their utilization in dye removal from aqueous media were investigated. Fe3O4 magnetic nanoparticles were synthesized by adding 1:2 ratio of Fe+2/Fe+3 to an aqueous solution, maintained in an inert atmosphere at a high pH. With the highly hydrophilic graphene oxide sheets and positively charged surface of the Fe3O4 nanoparticles, the nanocomposites were synthesized through electrostatic interaction in aqueous solutions. The nanocomposites were characterized by TEM, XRD, FT-IR, and UV-Vis. The adsorption properties of the Fe3O4/GO nanocomposites toward Congo Red as an anionic dye and Methylene Blue as a cationic dye in aqueous solutions were investigated.