A heat exchanging tube unit is disclosed. According to one embodiment of the present invention, the heat exchanging tube unit comprises: a first tube unit wherein a fluid moves and a first heat exchange pin is mounted in an outer longitudinal direction; a second tube unit, wherein a second heat exchange pin is mounted on the same line with the first heat exchange pin in the outer longitudinal direction while facing the first heat exchange pin, spaced from the first tube unit; and a gradient unit wherein a thickness of the first and second heat exchange pins are reduced from the first and second tube units toward an outer end part thereof.
