This work introduced a new electrochemical device for the synthesis of Fe3O4 magnetic nanoparticles. It is established based on a scarified rotating cylindrical Fe anode in an alkaline aqueous medium, at room temperature, in the presence of NaCl, without any chemical agent or surfactant. This technique is easy to scale up and controllable, so that by changing the parameters such as the rotating speed, current density, electrode interval, and electrolysis time, the size and morphology of the particles can be changed. The physical properties of the Fe3O4 nanoparticles, were characterized by FT-IR, SEM, VSM, DLS, and XRD methods. From the standpoint of environmental sustainability and economic efficiency, this technique's use of water as both a solvent and reactant (OH- generation), safe and cheap reagents, electricity instead of chemical reagents, room temperature and pressure, short reaction time, and scalability. (C) 2019 The Electrochemical Society.