We report a facile synthetic strategy for the in-situ growth of high-quality Prussian blue nanocubes (PBNCs) at the amine functionalized silicate sol–gel matrix (TPDT)–RGO composite via the electrostatic interaction. Subsequently, Pt nanostructures are electrodeposited onto the preformed ITO/TPDT–RGO–PB electrode to prepare the RGO/PB/Pt catalyst. The significance of the present method is that the PBNCs could be in-situ grown by inter-connecting the RGO layers, led to 3D cage-like porous nanostructure. The modified electrodes are characterized by FESEM, EDAX, XRD, XPS and electrochemical techniques. The RGO/PB/Pt catalyst exhibits the synergistic electrocatalytic activity and high stability towards the methanol oxidation. The porous nature of the TPDT and PB, and unique electron transfer mediating behavior of PB integrated with RGO in the presence of Pt nanostructures facilitated synergistic electrocatalytic activity for methanol oxidation.