A　mathematical　model　has　been　built　and　large　eddy　simulation　(LES)　method　is　adopted　to　predict　smoke　propagation　in　the　tunnel　between　the　Ji-Shuitan　and　Gu-Lou　subway　stations　in　order　to　make　fire　risk　assessment　of　tunnel　fire　in　subway　systems.　This　tunnel　is　a　representative　subway　tunnel　between　two　stations　in　the　loop　line　of　Beijing　Subway　Systems.　The　mass　concentration　distributions　of　smoke　at　different　heights,　smoke　horizontal　movement　distance,　spreading　velocity　under　different　operating　schemes　of　tunnel　exhaust　fans　are　predicted.　The　smoke　exhausted　effects　of　tunnel　ventilation　fans　are　also　testified.　The　results　show　that　the　existing　smoke　exhaust　system　could　reach　the　critical　tunnel　ventilation　velocity　under　5.0　MW　fire　condition　and　the　smoke　layer　could　be　kept　at　a　safety　height　for　passenger　evacuation.　The　simulated　results　can　be　provided　as　a　reference　for　tunnel　reconstruction　and　devising　passenger　evacuation　scheme.