Abstract <p>Previous artificial oxygen carriers mainly rely on the reversible combination of five coordination of porphyrin iron and oxygen to achieve oxygen carrying function. However, another oxygen-carrying mode, the competitive binding between oxygen and other ligands, has rarely been studied. In this study, heme dimethyl ester [HDME(II)] was used as the oxygen-carrying component to study the oxygen-carrying properties of its hexacoordinated complexes. The oxygen absorption capacity of the hexacoordinated complexes was determined by gas absorption method. At the same time, the oxygen absorption capacity was used as an indicator to investigate its s oxidation rate. The results show that in the five and six complexes of HDME(II), when there is a strong ligand, the hexa-coordinated complexes can effectively coordinate oxygen. When there is a strong ligand and a weak ligand at the same time, the oxygen binding capacity of the hexa-coordinated complexes is significantly improved. In addition, when the weak ligand is fixed and the strong ligand is changed, it can be observed that the coordination ability of the strong ligand has a significant effect on the oxygenation curve of the system. In addition, the long hydrophobic chain of the axial ligand in the HDME(II) hexacoordinated complexes helps to slow down the oxidation rate of the hexa-coordinated complexes. When the axial ligand has a certain reducibility, the oxidation rate of the hexacoordinated complexes is further reduced. Therefore, the oxygen carrier mode of the heme derivative is expected to become an effective oxygen carrier.</p>