In the present paper, we report the synthesis of Cetyltrimethylammonium Bromide (CTAB) and Sodium dodecyl sulfate (SDS) assisted Zirconia (ZrO2) nanoparticles by co-precipitation method. The effect of surfactant concentration on the structural and dielectric properties has been extensively studied. Xray diffraction studies reveal the formation of tetragonal phase in the ZrO2 nanoparticles prepared by lower CTAB concentration. However, for higher concentration of CTAB some traces of monoclinic phase appeared along with tetragonal phase. SDS assisted nanoparticles shows crystalline tetragonal phase with lower concentration of SDS and amorphous nature with higher concentrations of SDS. FTIR results show the presence of Zr-O symmetrical stretching vibrations at tetrahedral site. The dielectric properties of all samples have been studied from 10 Hz to 1 MHz, revealing the low value of dielectric constant with CTAB and very high value with SDS as compared to bare ZrO2 nanoparticles. The dielectric behaviour of the bare and surfactant assisted nanoparticles has been correlated with the phase transition, size of nanoparticles and the nature of surfactants. (C) 2016 Elsevier B.V. All rights reserved.