Chelating agents have potential effects on different properties of nanoparticles. Fe3O4 nanoparticles were synthesizes Using coprecipitation technique and oxalic, citric, stearic and lauric acids with concentrations of 0.5, 1, 2, and 5 vol% were utilized as the chelating agents. Subsequently, stability, structural, and magnetic properties of the samples were studied using measurement of zeta potential as well as FT-IR, XRD, DLS, TEM, and VSM analyses. It was found that the lower end of the size range was achieved for all samples utilizing 2 vol% chelating agents. So, in the present study, it was chosen as the optimum volume percentage of the chelating agents. Furthermore, for the nanoparticles treated with oxalic and citric acids, particle sizes were lower and the zeta potentials were larger comparing to those treated with stearic and lauric acids, which is an indication of their higher stabilization ability. Finally, the type of chelating agents had negligible effects on the structural and magnetic properties of the synthesized nanoparticles. (C) 2016 Elsevier B.V. All rights reserved.