The substitution of trivalent aluminium in Sr-Y type hexaferrite is considered to be an important for the enhancement of its magnetic and electrical properties. A series of single phase polycrystalline samples with chemical composition Sr2Zn2AlxFe12-xO22 (x = 2-10) were prepared by high temperature solid state reaction technique. The formed samples were analyzed with the help of X-ray diffractometer for single phase without the traces of ambiguous reflections. It is found to have hexagonal Y type structure with space group R3m. the helium Picnometric real density nearly agrees with X ray density. The electrical conductivity and magnetic susceptibility measurement was carried out over the temperature range 400-800K. It shows semiconducting behavior with dual conduction mechanism for higher iron concentration. Magnetic study of the compounds was performed by Gouy’s method. The Curie temperature TC and Curie molar constant CM of the compounds was found to be decreasing with increase in aluminium concentration.