NaCsZn0.5Mn0.5P2O7 powders were prepared by solid state reaction method. The study of the powder structure was conducted by X-ray diffraction (XRD) in temperature range from room temperature (RT) to 700K. Rietveld analysis of XRD patterns showed that obtained NaCsZn0.5Mn0.5P2O7 is a mix of three phases: orthorhombic (s.g. Cmc21) NaCsMnP2O7, monoclinic (s.g. P21/n) NaCsZnP2O7 and monoclinic (s.g. P21/n) Cs2MnP4O12. In the temperature ranges (400–500)K and (500–600)K the anomalies of lattice parameters for the NaCsMnP2O7 and Cs2MnP4O12 phases respectively were found. The electrical properties of the sintered ceramics were investigated from RT to 700K and in the frequency range 10–3×109Hz. The anomalies of electrical conductivity, dielectric permittivity and dielectric losses in investigated temperature ranges in these ceramics were found. This phenomenon can be associated with disordering in the lattices of NaCsMnP2O7 and Cs2MnP4O12 compounds.