In situ polymerization of ethylene with pretreated GNP by employing late transition metal catalyst (α‐diimine nickel), diminished the rate of reaction comparative with polymerization without GNP. Exfoliation of GNP consumed MAO for the treatment of new surfaces that caused reducing MAO concentration. Accordingly, the number of active centers of catalyst decreased. Subsequently, the molecular weight and the branching density of polyethylene changed. Moreover, the improvement of electrical conductivity, storage modulus, loss modulus, and complex viscosity observed with the increment of GNP weight fraction.