To provide a mask for emergency use which prevents poisonous gases and dusts from infiltrating into the mouth and the nostril when generated in emergency cases such as fires or earthquakes.

A bag 2 is made of a sealing material having a sealing means 6 openable at an opening part 3 and a mask body 1 comprising a water- absorbable material and a small bag 4 made of a sealing material with a less strength than that of the material of the bag 2 sealed up with water 5 added with a preservative are housed into the bag 2. Sealing is made by the sealing means 6 while external forces are applied on the bag 2 in case of emergencies to tear the small bag 4 so that the mask body 1 is impregnated with the water 5 in the small bag 4.