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The BaNdTiCrO (0 ≤ z ≤ 3.0) ceramics were prepared using the solid-state reaction route. The influence of substitution of Cr for Ti on microstructure and microwave dielectric properties of BaNdTiCrO (BNTC z) ceramics was investigated in this study. The X-ray diffraction patterns (XRD) of the specimens showed that pure BaNdTiO phase with tungsten bronze structure existed for z ≤ 1, but the secondary phase BaTiO was observed for 1.5 ≤ z ≤ 3. The substitution of Cr for Ti was confirmed by the results of scanning electron microscopy and energy dispersive spectrometer. The dielectric constant ( ε ) was deteriorated with the increment of substitution which was in accord with the tendency of apparent density. The quality factor value ( Q× f) was improved by a small amount of substitution for z ≤ 0.5, but deteriorated seriously when excessive Cr content was added ( z > 0.5). The temperature coefficient of the resonant frequency ( τ ) was effectively reduced from + 63 ppm/°C to − 7.1 ppm/°C with the increase of substitution content. At last, the excellent dielectric properties with ε = 81.53, Q× f = 11,294 GHz and τ = + 39.2 ppm/°C were obtained as z = 0.5 sintered at 1420 °C for 2 h. [ABSTRACT FROM AUTHOR]