The invention relates to an air-tight door device good in airtightness. The air-tight door device good in airtightness is characterized by comprising an upper frame, a lower frame, a vertical frame, a movable sash, a locking mechanism, two pulley mechanisms, two upper guide mechanisms, two lower guide mechanisms and a plurality of sealing adhesive tapes, wherein the two pulley mechanisms are arranged at the bottom of the movable sash; the movable sash is arranged between the upper fame and the lower frame and makes the pulley mechanisms be arranged on a guide rail in a sliding mode; the two upper guide mechanisms are arranged between the upper frame and the movable sash; the two lower guide mechanisms are arranged between the lower frame and the movable sash; the vertical frame is arranged on one side of the movable sash; the locking mechanism is arranged between the movable sash and the vertical frame; and the sealing adhesive tapes are arranged between the side wall of the movable sash and the side wall of an upper baffle, between the side wall of the movable sash and the side wall of a lower baffle as well as between the end portion of the movable sash and the vertical frame. The air-tight door device good in airtightness has the advantages of being scientific and reasonable in structural design, good in sealing effect, convenient to install, not prone to having errors and the like.