The self-assembled SrM dot array on Au islands has been prepared at various substrate temperatures for underlayer by using DC magnetron sputtering system. C-axis oriented SrM perpendicular to the films can be observed only at substrate temperature for underlayer of room temperature. The intensity of (111) diffraction line for Au and that of (00l) diffraction line for strontium ferrite decreases with increasing substrate temperature for underlayer. The maximum of coercivity and remanent squareness ratio in perpendicular direction are 3.4 kOe and 0.6, respectively, at substrate temperature for underlayer of room temperature.