In the present study, α-NaCuPO4 compound was prepared by solid-state reaction method and characterized by X-ray powder diffraction and infrared spectroscopy. The AC electrical conductivity and dielectric relaxation properties of this compound have been investigated by means of impedance spectroscopy measurements over a wide range of frequencies and temperatures 209 Hz–1 MHz and 598–708 K, respectively. Both impedance and modulus analysis exhibit the grain and grain boundary contribution in the electrical response of the sample. It was found that the data of the AC measurements follow the overlapping large polaron tunneling model and the model’s parameters were determined.