A solar-driven thermoelectric ventilator was designed, by adjusting the input voltage of the thermoelectric ventilator to adapt the requirement of fresh air load varied with times.The capacity matching relationships among PV modules, thermoelectric ventilator and battery were analyzed, and the corresponding numerical model was also developed.The working condition of thermoelectric ventilator for an office with a fresh air of 90 m3/h at 8:00 to 18:00 in Beijing from July 21st to August 21st and from January 1st to 31st was simulated.The simulation results show that during the simulation period, the total output of PV modules was 9424 kW, and the total electricity consumption of thermoelectric ventilator was 6435 kW, the maximum power consumption of continuous rainy weather was 119 kW, and the system’s average cooling COP can reach 250 from July 21st to August 21st.The total output of PV modules was 5029 kW, and the total electricity consumption of thermoelectric ventilator was 4054 kW, the maximum power consumption of continuous rainy weather was 151 kW, and the system average heating COP can reach 302 from January 1st to 31st.