Chemically regenerative redox fuel cells (CRRFCs) using liquid catalysts as an alternative to solid-state cathode catalysts have been intensively studied. Here, we studied Fe2+/Fe3+ as a liquid catalyst with Fe-macrocycles as a cocatalyst in CRRFCs. The Fe2+-oxidation rate was enhanced in the presence of Fe-Phthanolocyanine. The single cell having the cathode supplied by the liquid catalyst with Fe-Pc showed a maximum power density of ∼249 mW cm–2.