Polymer nanocomposites have received considerable attention in recent years as an effective method of enhancing polymer properties. Polymer/graphene (e.g., from expanded graphite) nanocomposites represent promising materials owing to their conductive and barrier properties. However graphene nanofillers tend to aggregate extensively as a result of intensive pi-pi electronic interactions, making the preparation of the targeted “exfoliated” nanocomposites very challenging. To improve their processing, graphite particles can be oxidized and then chemically or thermally reduced at high temperature resulting in higher extents of carbon nanosheets exfoliation throughout the polymer matrix. In this work, several types of surface treatments were investigated on expanded graphite, i.e., TIMREX BNB90 from TIMCAL Cie, to improve their dispersion ability into poly(m-xylylene adipamide) (MXD6) selected as polymeric partner. This semi-aromatic polyamide matrix as produced through condensation of meta-xylylene diamine with adipic acid was selected for its engineering applications. The expanded graphite surface treatment involved a supramolecular approach via the use of pyrene-based surfactant and graphene oxides (GO) generated from TIMREX. Their reduction was performed either with hydrazine (Chemically Reduced GO; CRGO) or via thermal reduction carried out at relatively low temperature, i.e., at 240°C (Thermally Reduced GO; TRGO). Afterwards, taking advantage of the condensation-type polymerization, graphene-filled polyamide masterbatches were prepared in order to further enhance the dispersion extent of the as-modified graphene nanoparticles within the MXD6 in bulk conditions (in absence of any solvent). Then the masterbatches were re-dispersed into the commercial MXD6 using a twin-screw microcompounder. The thermal, mechanical, electrical and rheological properties of the composites were determined to assess the improvement of the graphene dispersion quality within the polyamide.