Optically transparent counter electrodes outperforming the conventional Pt counter electrodes in dye sensitized solar cells (DSSCs) are seldom reported. In this work, a highly transparent (∼88% at 550nm) and catalytic (charge transfer resistance <1Ωcm 2 ) counter electrode based on a novel Pt—polyelectrolyte functionalized graphene composite is demonstrated. Graphene sheets (HEG) are synthesized by hydrogen induced simultaneous exfoliation–reduction of graphite oxide. HEG is functionalized by a cationic polyelectrolyte, poly-diallyl-diammonium chloride (PDDA) which causes minimum damage to graphene and assists in uniform tethering of nanoparticles. Pt nanoparticles are decorated on PDDA-HEG by a simple microwave assisted polyol reduction method. Electrochemical impedance measurements and cylic voltammetry measurements show that the higher catalytic activity of Pt/PDDA-HEG is due to the presence of positive charges and nanostructured Pt. As a consequence, the DSSCs fabricated with Pt/PDDA-HEG counter electrode exhibits an enhanced power conversion efficiency of ∼5.7% as compared to ∼4.5% for reference cells with Pt counter electrode.