Barium hexaferrites with the general formula Ba1-xSrxFe12O19(x=0.1, 0.3, 0.5, 0.7, 0.8, 0.9) were synthesized by the citrate method and annealed at 1100 0 C for 2 hours. The structural and magnetic characteristics were studied by X-ray diffraction (XRD), scanning electron microscopy (SEM), and vibrating sample magnetometer (VSM) techniques. XRD patterns confirmed the formation of BaSr-M phase in addition to the non-ferromagnetic intermediate phase (α-Fe2O3). The magnetic properties such as saturation magnetization (Ms), remanence (Mr), squarness ratio (Mr/Ms) and coercivity (Hc) were calculated from hysteresis loops. The magnetic properties of the Ba-ferrite were remarkably modified due to the substitution of Sr, this suggests that the materials under investigation are suitable for different applications requiring high temperatures.