La1-xTbxFeO3 nanoparticles (where x=0.00, 0.02, 0.04, 0.06, 0.08) prepared via micro emulsion method were characterized by Thermogravimetric analysis (TGA), X-ray diffraction (XRD), Scanning electron microscopy (SEM) and Fourier transform infra-red spectroscopy (FTlR). According to TGA analysis, the phase formation temperature identified was about 989 degrees C. Both XRD and FTIR confirmed the orthorhombic structure of La1-xTbxFeO3 nanoparticles. The crystallite size estimated by XRD was in the range 40-75 nm. The cell volume measured by XRD was found to decrease upon substitution. The general trend deviated for x=0.08. The SEM analysis of nanoparticles estimated the particle size in the range 50-95 nm. After characterization the nanoparticles were subjected to the dielectric behavior evaluation in the frequency range 1 x 10(6) Hz to 3.0 x 10(9) Hz. Dielectric parameters were decreased by substitution of La3+ with rare earth Tb3+ ions. The dielectric studies showed the possible utilization of these nanomaterials in high frequency devices. (C) 2015 Elsevier Ltd and Techna Group S.r.l. All rights reserved.