Magnetic nanoparticles are effective delivery systems to target therapeutic genes by the attractive forces of magnetic fields. Curative effects depending on dose of nucleic acids or drugs increased, while cytotoxic effects minimized with these systems. In this study, a novel magnetic nanoparticle synthesis method was developed by combining advantages of microemulsion and multiple emulsion methods. Particle size, zeta potential, magnetization, complex formation with nucleic acids, DNase I protection ability, and cytotoxicity levels were examined. At last, magnetic nanoparticles were obtained with a promising synthesis method and it is determined that they are sufficiently small, non-toxic and have optimal surface properties for systemic delivery of nucleic acids.