Incorporation of nanoparticles in polymeric matrices can lead to unique dispersion states having the potential to create composites with enhanced mechanical, thermal, and electrical properties. In the present work, the rheological percolation behavior of high density poly ethylene (HDPE)/ Graphene Nanoribbon (GNR) nanocomposites has been investigated. GNRs are synthesized from nitrogen-doped and undoped multiwall carbon nanotubes via a chemical route using potassium permanganate and some second acids. HDPE/GNR nanocomposite samples were prepared through a solution mixing procedure. Different dispersion states are achieved using different synthesis methods providing different interparticle interactions and internal compartments. Linear and non-linear rheological response of prepared samples is captured over wide range of frequency and temperature in order to determine percolation behavior and network properties. Prolonged relaxation of flow induced molecular orientation and retarded elastic recovery are also observed due to presence of GNRs. Structural evolution of 3D percolated network of GNRs are also compared with polymer nanocomposites made with carbon nanotubes sample.