Because of the tremendous fire risks in tunnels, the firefighting designs of tunnels should first of all ensure the occupants' safety in case of fire incidents. Therefore, tunnel occupant evacuation model "Tunev" is developed. By means of the model “Tunev”, the total evacuation durations for cases in which fires occur at different tunnel locations can be predicted; by means of model “Tunev” assisted by fire simulation code CFD——POENICS3.5, the durations before hazards occur can be predicted; by means of comparing the two sorts of durations, the safety of the tunnel occupant evacuation can be determined. In the paper, the relevant concepts of model "Tunev" is presented, evacuation simulation is made for a tunnel by means of model "Tunev" and the validation and actual application of the model is described.