Fe3O4 nanoparticles have attracted extensive attention in the field of environmental remediation owing to magnetism, large specific surface, size and ease of recycling. However, the removal efficiency and mechanisms of doxorubicin hydrochloride (DOX) with as-prepared Fe3O4 nanoparticles are still not well understood. In this study, Fe3O4 magnetite nanoparticles were prepared by euphorbia cochinchinensis extract via the green synthetic route and used to remove DOX, an anti-cancer drug. The green synthesized Fe3O4 nanoparticles were characterized using TEM, XRD, BET, FTIR and magnetism techniques. Results revealed that green synthesized nanomaterials consisted of magnetite Fe3O4 having 10-30 nm particle size and exhibiting high specific surface area of 95.8m(2)/g. These Fe3O4 nanoparticles were employed to adsorb DOX from aqueous solution and the influences of initial pH, initial concentration of DOX and temperature were investigated. The results showed that 80.2% of DOX was removed using 20 mg/L of Fe3O4 nanoparticles at 303 K. Adsorption isotherms and kinetics data revealed that the removal of DOX fitted well to the pseudo second-order model and that the Freundlich adsorption model was a better fit than the Langmuir model. The probable removal mechanism of DOX on Fe3O4 was electrostatic interaction. Moreover, the application of Fe3O4 to remove DOX from real wastewater was evaluated.