The GaN-based nanoelectroceramics were produced using the sol-gel method and their variation with Ni at different atomic ratios (0%, 0.2%, 2%, 4%, 6%) was investigated. The surface morphology, structure, and optical and electrical properties of undoped and Ni doped GaN nanocomposites were characterized. The X-ray diffraction (XRD) results showed that the hexagonal Wurtzite lattice structure of the obtained samples was polycrystalline. The crystallite size of the nanopowders was calculated as 22.52, 21.36, 20.47, 18.36, and 17.96 nm for 0%, 0.2%, 2%, 4%, and 6% samples, respectively. The reflection spectra of the samples decreased with increasing Ni ratio. The optical band gap values of the samples calculated by using Kubelka-Munk function were found as 3.31, 3.29, 3.22, 2.99, and 2.88 eV for 0%, 0.2%, 2%, 4%, and 6% Ni samples, respectively. The electrical conductivity values of the samples were measured at the temperature range of 303–423 K based on the temperature and analyzed by Arrhenius equation. It was observed that Ni dopant decreased the activation energy values of GaN nanopowders. It was concluded in the light of the obtained data that the stability and the crystal structure quality of the Wurtzite-structure GaN produced in this study were high; therefore, this semiconductor material can be used in electrical and optical applications and structural and physical properties of these materials can be changed with Ni dopant.