To provide a dead body preservation method by which a dead body can be preserved in a coffin for a long period while preventing odors, decomposition, and aerial infection.

In the method, a dead body is preserved in a coffin 1. A hydrophilic bag 7 containing a chlorine dioxide generating agent 8 containing either sodium chlorite or potassium chlorite and a wet sheet 3 containing at least a water-absorbing resin 4 are disposed on a dead body 2 with the wet sheet 3 placed on the hydrophilic bag 7. Moisture absorbed in the water-absorbing resin 4 is given off from the wet sheet 3 to react with the chlorine dioxide generating agent 8 to produce chlorine dioxide gas in the coffin 1 for deodorization and disinfection.