Research on H-2 production has recently been directed to the development of cost-efficient and robust heterogeneous catalysts for hydrogen evolution reaction (HER). Given the promising catalytic activities of several cobalt-based systems and the robustness of Prussian blue analogues in harsh catalytic processes including water oxidation, a Co-Co Prussian blue analogue was investigated as a HER catalyst for the first time. Co-Co Prussian Blue modified fluorine doped tin oxide (FTO) electrode demonstrated a significant HER activity with an onset overpotential of 257 mV, a Tafel slope of 80 mV dec(-1), and a turnover frequency of 0.090 s(-1) at an overpotential of 250 mV. Comparative XPS, Infrared, and XRD studies performed on pristine and post-catalytic electrodes confirm the stability of the catalyst. Graphical Abstract [GRAPHICS] .