Provided is a trachea-insertable tracheal tube equipped with a tip section that is positioned on the lung side in the trachea, a base end section that is provided on the side opposite the tip section, and a luminous body having an airway-securing lumen that passes from the base end section to the tip section. In the trachea-insertable tracheal tube, there is a microstructure region positioned on at least part of an inner surface that forms the airway-securing lumen in the lumenal body. The microstructure region has a surface whereon protrusions and recessions that are from several tens of nm to several hundreds of nm in size are formed atop protrusions and recessions that are from several µm to several tens of µm in size, preferably several tens of µm in size, and it is difficult for phlegm to adhere to the tracheal tube.
