Ceramic samples of [Na0.5K0.5](1) (-) (x)(Li)(x)(Sb)(x)(Nb)(1 - x)O-3 (NKNLS) (x = 0.04-0.06) were prepared by high temperature solid-state reaction method. X-ray diffraction analysis of the powder samples suggests the formation of a single-phase material with transformation from orthorhombic to tetragonal crystal structure with increase in Sb content. Dielectric studies show a diffuse phase transition about 100 degrees C and another phase ferroelectric-paraelectric transition at 330 degrees C. Polarization vs. electric field (P-E) hysteresis studies show maximum remanent polarization (Pr similar to 0.66 C m(-2)) for composition x = 0.05. AC conductivity in the compound increases with increase in temperature which may be attributed due to oxygen vacancies and show negative temperature coefficient of resistance (NTCR) effect. (C) 2011 Elsevier Ltd. All rights reserved.