Permanent magnet Barium M-Hexaferrite, BaFe_12-x Cu_x O₁₉  was synthesized with  a wide range of x (x = 0.1, 0.2,  …, 3 and 4mole% respectively). The precursor was made by mixing BaCO₃ powder and Fe₂O₃  powder, whereas CuO powder was used as additive. The powders were mixed together by wet milling in distilled water medium for 20 hours. The powders  had been dried at a temperature of 100⁰C for 24 h before calcined at a temperature of 1100⁰C for 2 hours. The powders were then grained to prepare 400 mesh (38 µm) in diameter.  The samples density was determined by using Archimedes method, magnetic properties by using permagraph,  crystal structure by XRD-pattern and microwave absorbing properties using VNA. The hysteresis curve showed that the value of magnetic field ranging from  43.36 G to 100.42 G , remanence magnetic induction (Br) 20G-320G, coercivity (HcJ) 1.07 kOe to 9.22 kOe and energy production (BH) max from 0.05kGOe to 0.92 kGOe with a density from 3.82 g/cm³ to 5.2 g/cm³. The  effect of Cu doping tent to increase the value of density with an optimum magnetic properties at  x=0.3%mole.