To regulate interfacial interaction between the polyethylene (PE) and graphene oxide (GO), maleic anhydride grafted high density polyethylene (PE-g-MAH) was utilized to enhance interfacial interaction between PE matrix and GO particles. Moreover, as a comparative investigation, -aminopropyltriethoxysilane (KH550) was used to functionalize GO (f-GO) so as to improve the interfacial interaction between PE matrix and GO particles. Compared to the addition of the PE-g-MAH, the f-GO had better dispersion in the PE/f-GO composites, indicating that functionalization of the GO with KH550 was the most effective way to improve the dispersion of the GO. However, the gel point for the PE/GO composite was not observed because the fillers network was not formed in the PE/GO composite. Compared to the f-GO particles, addition of PE-g-MAH was efficiency to build network structure of the GO particles so that the electrical conductivity of the PE/GO composites can be effectively improved. Moreover, the electromagnetic interference shielding effectiveness (EMI SE) of the PE/GO composites with addition of PE-g-MAH (PE/M-GO) was consistently higher than that of the PE/f-GO composites, indicating that the PE-g-MAH can effectively improve the EMI SE of the PE/GO composites. In addition, the microwave absorption (SEA) was main shielding mechanism for the PE/f-GO, PE/M-GO, and PE/GO composites. POLYM. ENG. SCI., 58:1774-1781, 2018. (c) 2017 Society of Plastics Engineers