Luminescent transition metal complexes have attracted a growing interest because of their potential applications in various fields,such as chemosensors and photodynamic therapy.There have been many studies focusing on the complexes of transition metal including Iridium and Ruthenium.However,there are still some limitations to previous metal complexes including low phototoxicity,high dark cytotoxicity and inadequate solubility,etc.[1] Hypoxic tumours are a major problem for cancer photodynamic therapy.It is proved that photoredox catalysis can provide an oxygen-independent mechanism of action to combat this problem.[2] Therefore we synthesis several metal complexes based on terpyridine ligand and evaluate their biochemical properties for photocatalytic therapy.