This research is focused on the effect of the nickel doping ratio on γ-ray attenuation radiological parameters for five compounds of chemical compositions BaMn1-xNixO3 (x=0.1,0.3,0.5,0, and 0.9), named Ni1, Ni3, Ni5, Ni7, and Ni9, in energy range between 0.015 and 15 MeV utilizing Phy-X/PSD software. Radiation parameters (MAC, LAC, HVL, TVL, MFP, ACS, ECS, Zeff, Neff, Ceff, Zeq, EBF, and EABF) are evaluated. Most of parameters depend profoundly on the photon energy. For instance, MAC is reduced from 137 to 0.133 cm 2 /g and LAC is increased from 775.7 to 0.75 cm -1 with increasing Eph (0.015 -15 MeV). Additionally, HVL and TVL increase from 0.0009 to 0.9 and from 0.003 to 3 cm respectively in between that energy range. Also, MFP increases from 0.001 to 1.3 cm but Neff, Ceff, Zeff , ACS, and ECS, decrease from 4×10 24 -2×10 24 , 1.6×10 10 -0.7×10 10 , 32 -15 electron/g, 100×10 -24 -1×10 -24 , and 3.3×10 -23 -0.007×10 -23 cm 2 /g at the energy 0.015-15 MeV. Furthermore, Zeq value is 19.3. Additionally, the exposure and energy absorption buildup factors (EBF and EABF) are determined to be 1-1.2, 2.7-29, 1.3-1.7, and 3.15-22 at various penetration depths (1-40 mfp). These values are independence of Eph at low mfp but at 40 mfp they are changed from 3to29. Maximum buildup parameters site in middle energy range, 0.2-1MeV. In another side, Most of such parameters are dependent on the Ni dopants. FNRCS values are 0.85 cm -1 . The present samples exhibit greater radiological properties than that published previously. These investigations are critical for the development of utilized semiconductor as detectors, attenuators, and protection radiation in various radiation safety applications fields.