Electrically conductive polymer composites (CPCs) with segregated structure have attracted constant research interest for several decades due to its ultra low percolation concentration, superior electrical conductivity and reasonable electromagnetic interference (EMI) shielding effectiveness at low filler loadings. However, the fabrication of segregated metal/polymer CPCs with ideal metal conductive network remains a challenge owing to the high density and weak interface action of metal powders. In this work, we report a facile strategy to construct a nickel segregated conductive network in ultrahigh-molecular-weight polyethylene (UHMWPE) matrix by synthesizing nickel coated UHMWPE conductive particles via electroless plating, and then fabricating the conductive composite with this conductive particles by hot-press molding. A thin layer of nickel with tunable thickness (~500nm-5μm) can be prearranged on the surface of fine UHMWPE grain (~100μm) via electroless plating technique. The specific high melting viscosity of UHMWPE can ensure the nickel only selectively locate at the boundary between the polymeric matrix grain during the molding process. Therefore, a well connected nickel conductive network with segregate structure can be realized and provides the nickel/UHMWPE conductive composites with low percolation threshold (1.0 vol% nickel content) and highly conductivity. The conductivity of this nickel/UHMWPE composites can achieve 2648 S/m at the nickel content of only 2.58 vol%. The SEM observation of the nickel conductive network in the composites as well as the volume of dimensional index t=3.5 from percolation theoretical fitting suggest that the conductive network has a 3-D structure, and the distribution of nickel in the UHMWPE matrix could have a “honeycomb-like” stacking architecture. This result indicates the segregated nickel/UHMWPE composites may posses a high efficient EMI shielding property and have potential application in EMI shielding field.