In this present work, the physical characteristics of the graphene/MWCNTs composite have been studied. Surface modification has been done by grinding process and acid treatment where planetary ball milling (PBM) machine for grinding in aqueous circumstance and a mixture of HNO3 and H2SO4 for acid treatment have been executed. Though, there are many researches of GN and MWCNTs nanoparticles based on individually as well as combined with other nanoparticles have been accomplished, reports on the combination of these two nanoparticles are negligible. In this paper, IR thermography, morphological and structural characteristics of modified GN-MWCNTs by field emission scanning electron microscopy, Raman spectroscopy and dispersibility analysis by sedimentation, UV-Vis spectroscopy, electric conductivity and thermal conductivity measurements have been presented in order to report the characteristics of GN/MWCNTs composite. Acid treatment as well as wet grinding of GN/MWCNTs composite at 500 rpm for 2 h gives the highest thermal conductivity enhancement which is 4.29% at 40 degrees C. (C) 2016 Elsevier Ltd. All rights reserved.