Abstract: The invention relates to an improved blast furnace distributing device with a nitrogen sealing structure which belongs to the field of blast furnace. The nitrogen sealing structure is divided into two functional areas on whole structure, wherein a labyrinth structure is arranged at position close to lower side of a blast furnace, which can achieve dustproof and dust falling effects, increase gas pressure resistance loss inside a furnace, and provide favorable conditions for sealing of an upper floating ring; the floating rings which are matched with one another are arranged at position close to upper side of the distributing device can be kept in contact all time through self-adaption in operation process, and achieve tighter combination through mutual running-in, so the structure does not require high-precision manufacturing cost.