In this contribution, Sr and Mn co-doped Bi0.90Sr0.10FexMn1 − xO3 (X = 0, 5%, 10%, 15%) nanoparticles were prepared by sol-gel (chemical route) method to observe the dominance of co-substitution on their grain size, morphology, UV-vis absorbance and magnetic properties. Co-substitution of Sr and Mn in BiFeO3, leads to structural transformation from rhombohedral (R3c) to orthorhombic (Pn21a). Field emission scanning electron microscope reveals that upon Mn doping nanoparticles become finer. The M-H loops depict that at 15 mol. % Mn doping the saturation magnetization (Ms) is enhanced significantly. Moreover, the synthesized nanoparticles absorb visible light and their band gaps reduce substantially.