Maltol complexes with zinc and iron were synthesized via the hydrothermal method, and the thermody-namic characteristics as well as antibacterial properties of the products were investigated by means of electronicspectroscopy, DSC and pour plate method. The results show that the coordination reaction between maltol andFe(Ⅲ) or Zn(Ⅱ) influences the absorption peak at 320nm and results in a 20-or 45-nm blue shift of the elec-tronic spectrum, which confirm the occurrence of the coordination reaction. DSC results indicate that the two com-plexes both have one narrow exothermic peak with the peak value of 293.9 and 143.9℃, respectively, and that theenthalpy values calculated from the DSC curves are respectively about 122.8 and 374.6 J/ g, which means thatmaltol-Fe is more stable than maltol-Zn. Moreover, the results obtained by pour plate method and optical densitymethod show that maltol-Fe is of more excellent antibacterial property in the order of Micrococcus luteus>Escherichiacoli>Bacillus subtilis >Staphylococcus aureus. The possible antibacterial mechanism of the complexes is also dis-cussed in the end.