The evaluation of various ventilation strategies for optimal thermal comfort design in terms of predicted mean vote index was investigated. The major parameter is the inlet/outlet diffuser's locations in the occupied region. The location effects of the inlet and outlet diffusers at the ceiling/walls on thermal comfort were examined every 0.4 meter. Eight different air distribution systems including single inlet- single outlet and single inlet- double outlets arrangements were studied in an indoor environment. Also, an experimental validation was conducted. The comparison results between prediction and test are quite well.