Epidemic viruses seriously affect human health and the normal operation of society, so it is particularly important to effectively kill viruses. In this work, the thermal performance of a thermoelectric air disinfection system are studied. Utilizing the characteristics of semiconductor thermoelectric sheets with both cold and hot ends, the system can increase the air temperature by heating (cound be used in sterilization), and then, reduce the temperature of the air by cooling. The measurement results show that the air temperature can be increased to 80 ℃ first, and then cooled to 35 ℃. The total energy utilization rate of the system can reach up to 1.2. In addition, combined with the measurement results and numerical calculations, the parameters such as the number of thermoelectric element series, input power, air flow, and boundary insulation can be used to analyze their effects on the system performance. The system may have broad potential applications in public health, medical care, and household disinfection.