The polycrystalline NaMgPO₄ ceramic, synthesized via a high-temperature solid-state reaction route, has been characterized by using different experimental procedures. The X-ray powder diffraction confirmed the phase formation of the synthesized compound in the orthorhombic phase. It assumed an olivine-type structure made up of corners linked between tetrahedral PO₄ and octahedral NaO₆ and MgO₆ groups. Infrared and Raman spectroscopies confirmed the presence of PO${}_4^{3-}$ groups. Local structure and chemical bonding between MgO₆ octahedral and PO${}_4^{3-}$ tetrahedral groups investigated by diffusion Raman is the feature in the phase transition at $T=$ 693 K. The temperature dependences of the real $𝜀\prime$ and imaginary $𝜀\prime$ parts of dielectric permittivity show a distribution of relaxation times. From Nyquist plots, the presence of grain and grain boundary effect in the material is noticed. The impedance spectroscopy measurement showed a non-Debye-type process. From the impedance data, the determined grain resistance reduces with increment of temperature showing negative temperature coefficient of resistance (NTCR)-type nature of the material which also confirmed from conductivity analysis. The temperature dependence of ${\sigma }_{\mathrm{\text{dc}}}$ reveals an Arrhenius-type behavior with two activation energies, 0.98 eV in region I and 0.67 eV in region II. Studied sample’s conduction is assured by Na${}^{+}$ ions’ hopping in tunnels and its mechanism was discussed.The polycrystalline NaMgPO₄ ceramic, synthesized via a high-temperature solid-state reaction route, has been characterized by using different experimental procedures. The X-ray powder diffraction confirmed the phase formation of the synthesized compound in the orthorhombic phase. It assumed an olivine-type structure made up of corners linked between tetrahedral PO₄ and octahedral NaO₆ and MgO₆ groups. Infrared and Raman spectroscopies confirmed the presence of PO${}_4^{3-}$ groups. Local structure and chemical bonding between MgO₆ octahedral and PO${}_4^{3-}$ tetrahedral groups investigated by diffusion Raman is the feature in the phase transition at $T=$ 693 K. The temperature dependences of the real $𝜀\prime$ and imaginary $𝜀\prime$ parts of dielectric permittivity show a distribution of relaxation times. From Nyquist plots, the presence of grain and grain boundary effect in the material is noticed. The impedance spectroscopy measurement showed a non-Debye-type process. From the impedance data, the determined grain resistance reduces with increment of temperature showing negative temperature coefficient of resistance (NTCR)-type nature of the material which also confirmed from conductivity analysis. The temperature dependence of ${\sigma }_{\mathrm{\text{dc}}}$ reveals an Arrhenius-type behavior with two activation energies, 0.98 eV in region I and 0.67 eV in region II. Studied sample’s conduction is assured by Na${}^{+}$ ions’ hopping in tunnels and its mechanism was discussed.