Polypyrrole (PPy) was used to obtain a coating on magnetite (Fe3O4) and hematite (Fe2O3) iron oxide nanoparticles (IONPs). PPy was synthesized on the surface of IONPs by admicellar polymerization for enhancement of electrical conductivity. Low surfactant and monomer levels enabled formation of films on the order of 1 nm thickness. The hydrophobic tendency of the modified IONPs was observed by aggregation in water and exclusion of water molecules. Coated IONPs were characterized by Fourier transform infrared spectroscopic techniques (FT-IR) and scanning electron microscopy (SEM) with particle size distribution analyzed by dynamic light scattering (DLS). Thermal stability of PPy-coated IONPs was investigated by thermogravimetric analysis (TGA). Lastly the magneticity and electrical conductivity of the modified IONPs were analyzed by VSM and multimeter measurements of packed IONPs in a circuit, respectively. Modified IONPs significantly enhanced electrical conductivity with greater effect related to the amount of PPy film coated on the IONP surface. Particle sizes of magnetite and hematite were found within the range between 50 and 2000 nm, depending upon PPy coating. The electrical property was successfully improved, but magnetic properties were not statistically different from the bare IONPs. The concentration of Py monomer at 30 mM shown as the critical concentration of both magnetite and hematite had the achievement of the high electrical conductivity.