Abstract This study examines the thermal properties of graphene reinforced polylactic acid nanocomposites prepared via the non- conventional spark plasma sintering (SPS) technique. The nanocomposites were developed having weight percentage of GNP (0- 7wt%) with PLA. SPS processing under 25 MPa,160 deg. C,20 deg. C/min and 10 min. GNP peak were observed around 26.5 deg. for all nanocomposites in the X-ray diffraction (XRD).The thermal stability of the sintered nanocomposites were investigated via thermogravimetric analysis (TGA),fourier transform infrared (FTIR) and differential scanning calorimetry (DSC) analysis. A marginal improvement was observed in the crystallinity and melt temperature of the consolidated nanocomposites with respect to pure PLA. The thermal stability of PLA was observed to have extended to 400 deg. C via the process of sintering. The residual content of PLA/GNP nanocomposites is higher than pristine PLA at 600⁰C. The glass transition temperature reported by the dynamic mechanical analysis on the nanocomposites shows an improvement in thermal stability compare to DSC report. This indicate that DMA is highly sensitive to local segmentation motion than DSC. Higher stiffness was also observed with an increasing amount of GNP content in the matrix. The related behaviour and the marginal differences noticed with the increasing GNP content in the nanocomposite suggest a stronger impact of the sintering process above the GNP content on the thermal performance of the nanocomposite.