The invention discloses a near-infrared wide-spectrum metal complex dye. The structural formula of dye molecules is [M-BL-M], wherein a metal ion M forms a metal building block with surrounding ligands; BL is a bridging ligand; a delocalized pai orbit is formed between the metal building block and the bridging ligand; the bridging ligand has good conjugation performance and electronic conductivity; the charge distribution of the dye molecules is completely delocalized; when the metal building block receives energy stimulation, a strong valence state transition effect is generated in the dye molecules, and can be used for broadening the absorption range of a dye spectrum and ensuring that an absorption spectrum is red-shifted to a near-infrared area. The near-infrared wide-spectrum metal complex dye disclosed by the invention can be applied to dye-sensitized solar cells, and can be used for increasing the spectral response range of the sensitized solar cells, thus improving the photoelectric conversion efficiency of cells.