This　study　takes　a　subway　station　of　line　2　in　Beijing　as　study　object,　based　on　the　piston　wind　flow　characteristics　of　a　field　test　and　a　1:8　scale　model　experiment　combining　the　theoretical　research　and　the　numerical　simulation,　specially　analyzed　the　influence　on　the　piston　wind　flow　characteristic　of　the　different　setting　heights　of　the　Semi-enclosed　platform　doors　(SPDs),　and　based　on　the　test　results　of　air　temperature　and　humidity　in　and　out　of　the　subway　station　analyzed　the　＂cross-ventilation＂　effect　of　piston　wind　and　evaluated　its　contribution　to　the　energy　consumption　of　the　ventilation　and　air　condition　in　subway　station.　Results　show　that　little　difference　in　the　piston-wind　volume　exists　when　height　of　the　SPDs　changes　[Enclosed　platform　doors　(EPDs)　or　Semi-enclosed　platform　doors　(SPDs)];　according　to　the　summer　weather　condition　of　the　large　day-night　temperature　difference　and　the　lower　enthalpy　in　Beijing,　a　SPD　can　improve　the　indoor　air　quality　and　reduce　the　energy　consumption　of　ventilation　and　air　condition　in　subway　stations　in　Beijing.