<p>A part of Zagros railway is located in Zagros Mountains which has various long tunnels since this railway passes through a mountainous, hard-to-pass area. Some characteristics of these tunnels include inadequate cross section and free space relative to the wagon size, arcs with small radius, location on the slope, lack of proper ventilation, and the lack of road access to the rescue. So, the necessity of research into possible fire in railway passenger trains in tunnels becomes clearer. The results showed that in the assessment of fire risks in passenger trains inside tunnels through FMEA model, two types of fire risks are encountered. The first type risk (prior to fire) included risks that can lead to fire in passenger trains, and the most important (first priority) of them are the high temperature of turbochargers of the generators, fire in the manifold of engine exhaust, and the spilling of fuel from the injector pump pipe assembly, and output connector hoses leading from the engine assembly. Also, the events that can happen after a fire in trains are not less important than the factors leading to fire. The most important and high risks especially in tunnels 22 and 23 of Zagros ( the longest tunnels in this area) are the immediate location of cliffs at the exit mouths of these tunnels to the exit of the tunnel, difficulty of the evacuation of passengers in case of fire, and the passengers&rsquo; rush to the exit doors.</p>