Abstract: Combining with movement theory of fire smoke flow of mine roadway and effect of fire-air pressure to ventilation network, the paper proposed mathematical model of numerical simulation and computer algorithm of smoke expansion in time of mine fire, and determined reasonable routes for avoiding disaster. Based on basic information platform of 3DGIS digital mine and 3D visualization technique, computer programs of algorithm of smoke movement and route for avoiding disaster were developed, and it can simulate process of fire disaster in mine and show the scope of smoke pollution and routes for avoiding disaster for workers. The algorithm can be applied to analyze smoke flow expansion of actual fire disaster confirmed by experiment of roadway physical miniatures. The program was applyed to fire emergency plans drills of a coal mine, and played a very good role and achieved a good result.