The invention discloses a closed circulating deoxidization device which comprises a main air inlet pipe, a deoxidization chamber, a main air outlet pipe, a feeding opening, a feeding chamber, a discharging chamber and a discharging opening, wherein an outlet of the main air inlet pipe is communicated with an air inlet in a side of the deoxidization chamber; an inlet of the main air inlet pipe is communicated with an air outlet in the side of the deoxidization chamber; the feeding opening is communicated with a deoxidant inlet in the top of the deoxidization chamber through the feeding chamber; a deoxidant outlet in the bottom of the deoxidization chamber is communicated with the discharging opening through the discharging chamber; a deoxidant supporting mesh is arranged in the deoxidization chamber, wherein the deoxidant supporting mesh is located at the bottom of the deoxidization chamber; an opening in the top of the deoxidant supporting mesh faces the deoxidant inlet in the top of the deoxidization chamber; an opening in the bottom of the deoxidant supporting mesh faces the deoxidant outlet in the bottom of the deoxidization chamber. The closed circulating deoxidization device has relatively good deoxidization effect.