To manufacture anisotropic plastic magnets with higher magnetic power, the compounding of Strontium Ferrite powder/plastics binder and injection molding processes should be optimized. In this study, we have carried out the optimization of injection molding machine design, and the mechanism analysis of the compounding operation. As a result, to generate effective strong magnetic fields during injection molding, the coiling system, mold structure, and pole shape were very important elements. Better Ferrite powder dispersion accelerated the particle orientation, which lead to higher magnetic power of the molded product when strong magnetic fields were applied. And then, particle dispersion depended on specific energy of the compounding machine unless excessive shearing force degraded Ferrite and plastics binder.