This paper reports on the synthesis of polycrystalline (Li,Ti)-doped NiO powders (i.e., LixTi0.1Ni1-xO, abbreviated as LTNO) by the solid-state synthesis method. Note that, the doping concentration of Ti is kept constant (x-0.10) in the stoichiometry, the difference in the material behavior of LTNO samples can only be attributed to the effect of Li. X-ray diffraction patterns confirmed a cubic rock-salt structured NiO-based phase with the presence of minor NiTiO3 phase, were reported elsewhere [Venkata et al., Chem. Phys. Lett., 649 (2016) 115-118.]. Dense microstructures were obtained using ultra high resolution scanning electron microscope. A high dielectric constant (epsilon similar to 10(4)) near room temperature at low-frequency was observed in LTNO ceramics. Weak temperature dependence of dielectric constant over the measured compositions (x = 0 to 0.10) was observed in the LTNO ceramics. A giant dielectric constant of 10(4)-10(5) at high temperatures (120-170 degrees C) for certain LTNO compositions (x = 0.15 to 0.3) was observed in the sintered ceramics. The origin of the high dielectric constant observed in these LTNO ceramics is attributed to the Maxwell-Wagner polarization mechanism and a thermally activated mechanism. (C) 2016 Elsevier B.V. All rights reserved.