The present work investigates fabrication and characterization of graphene/ poly (methyl methacrylate) (PMMA) composite flexible films. Graphene/PMMA flexible films were fabricated by one-pot alternate stirring sonication (OPASS) process. The method relies on the alternate high speed stirring and ultrasonication of graphite and its blending with PMMA without any sufactant assistance. A comparative study of the nanocomposite solution was carried out with the composite solution prepared by conventional (CL) method. The transformation of micro-sized graphite particles to nano-sized layers of graphite or few layer graphene was characterized by various analytical techniques. The electrical response of the fabricated flexible films were studied and exhibited an electrical conductivity of 44.92 S/m and 0.10 S/m with 50 wt% and 10 wt% concentrations, respectively. Thus, the fabricated flexible films could have excellent surface toughness, modulus and barrier properties, which make them a suitable candidate for commercial flexible electronic and wearable sensor applications.