[Purpose]For controlling the rising temperature, there are more institutions using air-conditioning. However, the indoor temperature is often too low to protect the health of residents. The aim of the study is to investigate the temperature distribution within a chosen institution filled with patients. There are three main objectives: 1. To assess whether the internal temperature of the environment is appropriate; 2. Establish an indoor airflow model to analyze the main factors of temperature distribution; 3. Consider possible engineering intervention.[Method]After measuring the space for evaluation and drawing a CAD model, we used CFD steady-state to analysis the velocity and temperature field. We use the AeroBox_2019 complex weather observation box to monitor temperature and humidity. After calculating the flow field distribution, the temperature and velocity obtained from simulation are used to calculate the thermal comfort index. Last, we compare our simulation data with the measured one.[Result]The current simulation shows that when the air conditioner is set to 23 ° C in the ward, the temperature near the human body is about 26-27 ° C while it is distributed unevenly in the rest of the space. In the corner of the ward, there’s 2° C higher than the sickbed near the door. The calculation results of the thermal comfort show that the ambient temperature of the environment is too low. [Conclusion]The poor design of the ventilation system used in this long-term care institution results in uneven flow field distribution, and the air conditioning design will cause uneven temperature distribution. The range of the deviation between the simulation and the measured data is about 0.05 showing our model is reliable. Thermal comfort results show that the temperature is too low and adjusting the air conditioner temperature is necessary. A ventilation system will be designed to improve such results.