In order to improve mechanical properties of the Al flake/pp composite used EMI shielding materials, Al flake is microencapsulated with LONPLY by phase separation method using organic solvent to improve the adhesion of Al flake/pp interface and the dispersion of Al flake in PP matrix. We assumed that the decrease of tensile strength can be minimized by microencapsulated method for Al flacke/pp composite. Shielding effectness(SE) was found to be 30dB when 15-18 v % of Al flake was added to PP matrix, and the volume resistively was measured as 100-10-1cm in both PP filled microencapsulated and non - capsulated AA flakes. Especially, when the attenuation was measured in 8$^{circ}$ 120Hz frequency range, for the sample with different thickness(1mm, 3mm) , we can be certainly observed reflection and transmittance.