This study focuses on the efficiency of passive solar chimney in natural ventilation performance. A case study is conducted for the conference hall at the Magic School of Green Technology (MSGT) in Tainan, Taiwan. The efficiency of the passive solar chimney is evaluated using both computational fluid dynamics (CFD) and full-scale model tests. Simulation and experimental results demonstrate that without the thermal resources of people in the conference hall. The air exchange rates were 5.15ACH and 4.92ACH. With the thermal resources of 200 people in the conference hall, the air exchange rates were as high as 8.62ACH. When the external temperature is lower than 28°C, the internal temperature in conference hall is still in acceptable and comfortable scope. By using the passive solar chimney in the conference hall, the air-conditioning system can be shut off for 4 months and energy consumption can be reduced by roughly 27% annually in Taiwan.