The utility model relates to a fire door device is prevented to underground power cable passageway, including preventing hot wall, sensing system, machine people's air defense fire door, the hinge, automatic door closer, electricity cable frame, the people's bank of china prevents fire door, thermal -insulated swelling agent, the normal close door closer, machine people's air defense fire door and pedestrian prevent that fire door is respectively through hinge and firewall connection, and through the control of opening and shutting of automatic door closer and normal close door closer, thermal -insulated swelling agent sets up around machine people's air defense fire door and people's bank of china prevent fire door's door frame, and with door frame closely adhesion of edge all around, automatically, expand rapidly and fill up door frame gap all around after the thermal energy agent when meeting with the rising of fire trouble temperature, keep apart the heat source in one side. Realization through above -mentioned technical scheme, the device provided by the utility model can prevent fire door's open and close movement according to the real -time condition in the power cable passageway to use the swelling agent to keep apart the burning things which may cause a fire disaster when being necessary, the cable and the relevant equipment of effectual protection power cable passageway have very high use value.