An open/close control system for an inspection lid adapted not to open while a vehicle travels. An emergency release device is provided behind the inspection lid, where the emergency release device disables power transmission of a driver which opens and closes a side entrance/exit door of a railway vehicle. The emergency release device is installed in a space inside a wall surface inside the vehicle, and the space can be opened and closed by the inspection lid. The open/close control system has a locking device provided in the space inside the wall surface in order to restrict rotation of the inspection lid, and also has an open/close controller which detects traveling of the railway vehicle to actuate the locking device.