To provide a method for producing a metal complex in which a ligand can rapidly be coordinated with a substitution-inactive metal ion to obtain the metal complex in high yield.

This method is to produce an organic ligand-containing metal complex from an inorganic metal complex and an organic ligand. Furthermore, the method for producing the organic ligand-containing metal complex comprises irradiating the inorganic metal complex and the organic ligand in the coexistence thereof with microwaves at ≥1 cm and ≤1 m wavelength.