The invention discloses an emergency blocking door, which includes two door frames. The two door frames are internally and externally fixed to a passage side by side, an outer gate and an inner gate corresponding to the two door frames are respectively arranged in the passage between the two door frames, the outer gate and the inner gate are respectively hinged to the passage supporting surfaces corresponding the bottoms, sides or tops of the door frames and driven by air bags, inflating depends on chemical reaction in the air bags during emergency and risk avoidance, explosive impact is produced to quickly push the inner gate and outer gate to close, and an emergency hazard source is closed on the side, which the gate is located on, of the passage. The emergency blocking door is differentfrom an emergency gate closing action of a traditional mechanical gate, reaction is faster, action is coherent, the anti-resistance ability is high, reliability and security are high, in addition, according to the emergency blocking door, after closing the door, the built-in high-pressure air bags and a supporting mechanism can squeeze the gates on both sides, sealing performance and strength ofgates on both sides are improved, the blocking ability of the blocking door is further improved, in addition, and anti-impact effect and stability are good due to the fact that vibration absorption capacity is high when the airbags inflate.