Frequency and temperature dependent impedance, dielectric and conductivity studies of NdCr1-xFexO3 (x=0, 0.2, 0.4, 0.6, 0.8, 1) perovskite ceramic nanoparticles in the frequency range 1Hz-1 MHz with various temperatures in the range RT-500 degrees C have been investigated. The NdCr1-xFexO3 (x=0, 0.2, 0.4, 0.6, 0.8, 1) perovskite ceramic nanoparticles have been synthesized by the sol-gel auto-combustion process. The structural investigations of the perovskite compounds have confirmed the single-phase orthorhombic structure with Pbnm space group by X-ray diffraction technique. The size of the crystallite has been determined by the Debye-Scherer formula; it is found to be 18-30 nm and increased with increase in Fe content. Impedance spectroscopy has been employed to investigate the frequency, temperature and composition dependent impedance, dielectric and conductivity of the compound. The existence of grain and grain boundary effects has been observed. The frequency dependence of dielectric data has used to investigate the conductive mechanism in the material. The NdCrO3 material shows high dielectric constant at room temperature in the order of 10(7) (giant dielectric constant) and decreased with increase in Fe content to the order of 10(3) at room temperature (C) 2017 Elsevier Ltd. All rights reserved.