Porphyrins fused to imidazolium salts across two neighboring β‐pyrrolic positions were used as N‐heterocyclic carbene (NHC) precursors to anchor AuI‐Cl complexes at their periphery. Synthesis of several thiolato‐AuI complexes was then achieved by substituting chloride for thiolates. Photodynamic properties of these complexes were investigated: the data obtained show that the Au−S bonds could be cleaved upon irradiation. The proposed mechanism to explain the release of thiolate moiety involves the S atom oxidation by singlet oxygen generated in the course of irradiation. In view of photodynamic therapy (PDT) applications, these porphyrins fused to NHC‐AuI complexes were tested as photosensitizers to kill MCF‐7 breast cancer cells. Results show the important role played by the ancillary ligands (chloride versus thiolates) on the photodynamic effect.