The purpose of this research is to examine the evacuation environments of passengers at a tunnel fire accident. The visibility of testees entered in the model tunnel on a fire, are investigated by the questionnaire. As a result, the following was clarified. It is thought that it is possible to evacuate to the first stage of a fire under stratified thermal smoke layer. However, it is thought that most testees cannot evacuate when smoke is filled around testees and the density of smoke Cs becomes about 0.3(l/m). Lighting equipments at the tunnel ceiling are not working at a fire.