Strontium hexagonal ferrites with compositional formula Sr0.85La0.15(NiZr)(x)Fe12-2xO19, where 'x' varies from 0.00 to 1.00 in steps of 0.25, were synthesized by auto-combustion method. Structural, magnetic, electromagnetic and microwave absorption properties of synthesized ferrites were studied. The vector network analyzer (VNA) was used to measure complex permittivity (epsilon'-j epsilon '') and complex permeability (mu'-j mu ''") in X-band (8-12.4 GHz) and Ku-band (12.4-18 GHz) frequency range. The minimum reflection loss curves were obtained using back metal plate method for analyzing absorption properties of the material. All the synthesized ferrites show maximum absorption in Ku-band for sample thickness in the range of 1.6-1.68 mm. These newly synthesized ferrites have great potential to be used as thin microwave absorber sheets with minimum reflection loss values in the range of -19.69 dB to -27.8 dB and bandwidth in the range of 680 MHz-1.25 GHz.