Nanosized Fe0.1Zn0.9Mn2O4 particles were prepared by hydrothermal method in absence and presence of surfactants. Transmission electron microscopy (TEM), scanning electron microscopy (SEM) and powder x-ray diffraction (XRD) techniques were employed for the characterization of the nanoparticles. Photocatalytic activity and electrical properties (DC- and AC-conductivity as well as dielectric constant) were studied. All samples showed spinel crystal structure with crystallite sizes depending on the preparation conditions and lays in the range of 11- 63 nm. The samples showed semiconducting behavior and the electrical conduction was explained by hopping mechanism in which the conduction occurred via electron exchange amongst transition metal ions situated on octahedral sites in spinel lattice. Influences of gamma radiation on the physical properties studied were investigated. Particle size, morphology, photocatalytic activity and electrical properties are influenced by the type of surfactant used in the preparation and affected by γ-irradiation process.