The impinging jet ventilation system (IJV) is one of the ventilation systems with high ventilation effectiveness systems, which creates temperature and contaminant stratification. The influence of exhaust opening locations on temperature and ventilation effectiveness in a room with IJV was studied using computational fluid dynamics (CFD). The height of the exhaust outlet location was changed as a parameter. As a result, it is shown that although the values of temperature and contaminant concentration at the occupied zone do not differ depending on the height, however, the height has a large impact on those at the higher level and residence time period of air.