Herein, we present an artificial photocatalytic system for H2 evolution based on a series of proton reduction catalysts, namely [Ni{S2C2(Ph)2}2] (1), [Ni{S2C2(Ph)2}2](NEt4) (1–), [Ni{S2C2(Ph)(Ph–OCH3‐4)}2] (2), [Ni{S2C2(Ph)(Ph–OCH3‐4)}2](NEt4) (2–), [Ni{S2C2(Ph–OCH3‐4)2}2] (3) and [Ni{S2C2(Ph–OCH3‐4)2}2](NEt4) (3–), [Ni(mnt)2] (NBu4) (4–), [Ni(mnt)(S2C2(Ph)2)](NBu4) (5–). These complexes are different of both in charge and the substituents on dithiolene ligand and represent a group of active catalysts for the reduction of protons with high TONs. A series of ReI complexes, [ReBr(CO)3 (bpy)], [ReCl(CO)3(bpy)], [Re(NCS)(CO3)(bpy)], [ReBr(CO)3(amphen)] and [ReBr(CO)3 (pq)] were used as photosensitizers, in combination with triethanolamine as a sacrificial electron donor and acetic acid as a proton source. The differences of the ligands in the electron donating properties and reactivity are discussed in the light of the experimental data. We also present the physicochemical characterization of a previously reported heteroleptic monoanionic complex (5–), by UV/Vis spectroscopy, FTIR spectroscopy, cyclic voltammetry and single‐crystal X‐ray diffraction studies.